The spin in the press seems to be "Labour win in spite of Corbyn" which is to be expected really. What has the guy got to do in order to be credited with something?
Well given that Corbyn was apparently barely featured in the Labour campaign, which seemed to centre around its, admittedly very strong, local candidate (one who seems about as un-Corbyn as it's possible to be in the Labour party for that matter), I'm not entirely sure how this can be attributed to Corbyn in any way.
I basically think Labour's good performance and UKIP fizzling is down to three factors. Firstly, as I've already said, Labour ran a very good campaign in the seat with a good candidate; second, Labour strategised well in attempting, as it always does, to maximise the number of people voting by post, which always seems to favour Labour. Finally, UKIP, on spite of all the bluster surrounding their campaign, were too thinly stretched on the ground, and failed to get out a lot of the people who voted for them back in May. Indeed, I suspect that a lot of UKIP's voters this time round actually voted for the Conservatives in the general election, which would explain the (rather predictable) collapse in the Conservative vote.