At time of writing (7.20am) every London Underground line with the exception of the Victoria Line has disruptions to service & suspensions.
Stansted and London City Airports are closed at the time of writing. Heathrow has only one runway open and even if you wanted to get there, you'd have problems as the Heathrow Express service has been suspended & the Tubes going there, err.... aren't.
Your best bet is to watch the news, listen to the radio and keep an eye on TfL's website, which was a mass of blue "suspensions" and "part suspensions" this morning.
The snow is expected to continue falling throughout the day, so there may not be much let up. 20cm of snow will be expected by the end of the day. Anyone from countries that get a lot of snow reading this blog or looking at #uksnow trending on Twitter, will think "What are they all moaning about, that's not heavy snow". But for a city that relies so much on public transport, whenever there's the wrong type of snow or too much of it, we're screwed.
That's the current view from my study window above, as regular readers know, my house backs onto a railway line and normally, I can see trains. But for the past half hour, there have been no trains!
Update: Made it to the station to be told, that I should have believed the view outside my house and there's no trains. Here's a few pictures from the snowy station
Absolutely tons of pictures on Flickr of the snowy Tube, but my favourite has to be of the, for once appropriately named, White City by pgchamberlin
2003 was the last time I can remember really heavy snow like this (I actually broke my leg in two places the next day falling on ice), and there were talks of us being prepared for it next time. Guess what? We're not.