Labour's revival in the opinion polls to the point where some polls are suggesting a hung parliament isn't as bad as it appears. At the end of the day the same underlying factors that put Labour 20-30 points behind are still in play and will reassert themselves over the long haul. In particular Gordon Brown's personality will drag Labour down.
I've said before that I do not believe surveys which claim that alternative leaders would do no better for Labour. Brown is insecure, secretive, hyper partisan and indecisive so I cannot see how replacing him with someone who is not could fail to benefit Labour in the long term.
Whilst the Conservatives need to be more coherent in dealing with the financial crisis they shouldn't be too worried at this point. By cementing Gordon Brown in place Labour's boost in the polls might be the most damaging blow they could have incurred.