It didn't take a lot of guesswork to find the site, at act.libdems.org.uk: and it turns out, it's just a Ning site with paid-for options to use your own domain name, remove any mention of Ning, and hide third-party adverts.

Here's the video intro to what it can do:

It's certainly a cost-effective solution: those 'pro' options are costing them £33/month at a guess, and make for a pretty rich social network. Ning also implements the OpenSocial protocols, so in theory there are ways to access and play with the underlying data - although they don't make it easy, at first glance. So although it's the cheap option, that doesn't necessarily make it a bad one.

But they may hit problems due to the inability to really customise the platform. Where you'd love to offer dropdown lists, for example a list of Westminster constituencies for event locations, all you get is a free text field for location: and searching isn't all that clever, so you'll need a lot of discipline to ensure consistent tagging.

Of course, it looks like what it is: a generic Ning site with a few LibDem logos stuck on it. So in that sense, it doesn't measure up to the Tories' custom-built MyConservatives.com. But if the site connects people, and those people go out and do things, it will have served its purpose, for a tiny amount of money.

• It's built on an open-source platform - specifically Drupal. Almost certainly the right choice: after all, Drupal describes itself as 'community plumbing'. For those who have never used it, Drupal is a startlingly powerful platform for all things social and online; but to me, that's its downfall - I've always found it overwhelming.
• It fell over on day one. Happens to us all.
• Opening the system to allcomers, not just party members, is a brave move - but the right one, I think. (And is something I suggested Labour might do with Labourspace, back in March 2008.)
• Having said that, the heavy Conservative branding - including the use of an Eric Pickles video on the homepage - will put a lot of people off. I don't see people registering for this unless they're at least passively Tory.
• The 'campaigns' page - currently the heart of the site - has two key elements: 'local campaigns' and an events calendar. Neither are working well. When I put my postcode into the local search - even though I live in a Tory-LD marginal, high on the LDs' list of target seats - it comes back: 'Your local candidate doesn't have a campaign team yet.' I'd have thought they'd pre-organise some of these key areas prior to launch. And there's no encouragement for me to sign up to be notified if/when they do finally organise locally. The events listing is rather curious, initially showing me events from 2 to 10 Oct - not great when today's the 13th.
• I really like the way they've illustrated what a donation pays for:
  
  It demonstrates that even a token donation can have a material effect...
• ... but I still think it's an uphill struggle to get people to donate. We're looking at a massive cultural change, at a time when public trust in politics really couldn't be lower. I just can't see it.
• The sign-up form isn't too intrusive, but it doesn't tell me what my details will get used for. Inevitably I'm assuming it'll go straight into their junk-mailing database - which is why I haven't signed up myself, incidentally.
• And whilst it may not be unique functionality - both Labour and the LibDems can rightly claim to have had a lot of the same tools for some considerable time - presentation and high-level commitment goes a long, long way. Even if it doesn't really raise the bar, the perception is that it does.
• I wonder what will happen to it after the election?