(Quick update: actually, not for all the United Kingdom as it turns out - the following method doesn't work for N Ireland. See Matthew's comment below.)

Here's a quick example, as much for my own future reference as anyone else's. Let's say you wanted to generate a map of a given MP's constituency - say Lynne Featherstone in Hornsey & Wood Green:

• You need to find the appropriate reference number for the constituency: either by browsing the list of all constituencies, or searching for places whose names begin with Hornsey. Note - these will produce nasty-looking data files, rather than pretty HTML lists. Hunt through the code, and you'll find:
  "65883": {"codes": {"unit_id": "25044"}, "name": "Hornsey and Wood Green", "country": "E", "type_name": "UK Parliament constituency", "parent_area": null, "generation_high": 13, "generation_low": 13, "country_name": "England", "type": "WMC", "id": 65883}
• The 'id' is the number you need - in this case, 65883. The MySociety API now lets you call the geometry of that area, in - among others - Google Earth's KML format, using the following URL. (Don't worry about the '4326' here: it's a reference to the coordinate system being used, and won't change in this context.)

  http://mapit.mysociety.org/area/4326/65883.kml

• Conveniently, Google Maps lets you enter a KML file's URL as a search query, and it will draw it on a map. Even more conveniently, if you add 'output=embed' as a search parameter, it strips away everything but the map itself. So here's an embedded map of Lynne's constituency, pulled into an <iframe>. Look at the source code, to see how easy it is.

Boundary data generated by MaPit.mysociety.org which contains Ordnance Survey data © Crown copyright and database right 2010; Royal Mail data © Royal Mail copyright and database right 2010 (Code-Point Open); National Statistics data © Crown copyright and database right 2010 (NSPD Open).

And thankfully, it bears a close resemblance to this map on Lynne's own website, which took me considerably longer to churn out.

The Prime Minister and Communities Secretary John Denham will today announce that the public will have more access to Ordnance Survey maps from next year, as part of a Government drive to open up data to improve transparency. Speaking at a seminar on Smarter Government in Downing Street ... the Prime Minister will set out how the Government and Ordnance Survey, Great Britain's national mapping agency, will open up its data relating to electoral and local authority boundaries, postcode areas and mid scale mapping information. The Government will consult on proposals to make data from Ordnance Survey freely available so it can be used for digital innovation and to support democratic accountability.

See that? Lots of definite statements, of how they will do this, will do that. Well, hold your horses. Ordnance Survey's rather brief press release is slightly more defensive, and markedly less excitable:

The Prime Minister has today announced that the public and others will have greater access to a range [of?] Ordnance Survey data from next year, as part of a Government drive to open up data to improve efficiency and transparency. The detail of this is still being worked through and a formal consultation period will begin in December to look at how these changes will be implemented.

So whilst DCLG see it as a chance to crowdsource some cool stuff, OS frame it purely in fairly boring accountant-bureaucrat terms. Hmm.

Of course it's welcome news, but there's a long, long way to go yet - and not much time to do it. With a general election on the horizon, boundaries absolutely must be freed - as quickly as possible, and in formats which will be most useful to the digital innovators. (Basically, that means dead easy integration with Google Maps.)

Oh, and let's not get carried away about 'postcode areas'. They aren't Ordnance Survey's to free, are they?

Over the last few weeks, I've been working with Ordnance Survey to produce a WordPress version of their new business strategy, published today. As you'll immediately spot, it's another piece of work based on Steph Gray's Commentariat theme, including some of the tweaks I did for BERR's Low Carbon Strategy.

As I write this, I've literally just pressed the 'go' button, so I haven't even read the document yet myself, and can't offer any opinion on it (yet). But I didn't hide my disappointment at the unveiling of the OpenSpace project a year ago, and I'm told things have moved much further forward on that front at least. It hasn't been enough to satisfy the Guardian's Free Our Data campaign, though.

I know this is a subject of considerable interest to the e-government / activist community, which probably covers most of you reading this. We've created a web-friendly platform for you to read what OS are proposing, and tell them what you think about it. What are you waiting for?

I've come across a rather curious anomaly in Google's new Street View. Southampton is one of the cities covered in the initial UK rollout... or rather, most of Southampton. You'll note the bizarrely unavailable stretch of Romsey Road... and the odd interruption of Wimpson Lane. Here's a link to it in Street View, to see for yourself.

So... who do you think operates from this unmapped building? If you need a clue, read this piece I wrote late last year: 'Ordnance Survey ban Google Maps'.

Of course, I'm sure there's a perfectly good reason.

On the face of it, that's brilliant news. But five months to do this? That's brave - especially when we're looking at some pretty fundamental legislative questions, as highlighted on the Power of Information blog last week. The Guardian's Free Our Data campaign blog has a few recent items along similar lines.

'OS OpenSpace allows you to build Web 2.0 applications using Ordnance Survey data' - just like Google. You can 'add markers, lines and polygons on top of Ordnance Survey maps, and also search for place names' - just like, er, you know. Oh, except that it's 'non-commercial use only'. According to their FAQ: 'There can be no advertising, paid promotional content or other revenue generating activities associate (sic) with any part of your website.' Which doesn't leave much.

There's a page listing various usage examples: but guess what? The examples are all non-interactive GIFs... which kind of defeats the object. Duh.

I'd love to get excited by this. OS is finally speaking the right language: API, web 2.0, mashup, etc. But they have to give developers a better reason to use this than their claim of having 'the best mapping data available'. They're already way, way behind.

Quick update: see comments from Ed Parsons - ex-OS, now 'the Geospatial Technologist of Google': 'not quite what I had opened Openspace would be, but given the constraints ... a great first step and will hopefully lead to the much needed rethink.'