I'd be hesitant to draw any firm conclusions from a one-off election, conducted under unusual circumstances. But the rise in Lib Dem support is eyecatching, and makes you wonder whether they're still taking votes from Labour, or whether, as Mike Smithson suggests, they are benefitting more generally from the increased visibility of being in government.
Another thing to note is the rise in UKIP support. They finished in fourth place with 6.6 percent of the vote, up from 3.1 percent in 2005. This could have been a popular response to the death of the previous UKIP candidate. But I wouldn't be surprised if the party enjoyed a minor influx of Conservative voters, disaffected by the coalition. Something to keep an eye on, but not something, I'm sure, which will unduly concern the Tories – particularly in those cases where their candidate scores over 50 percent of the vote.