Maybe more interesting vis-a-vis local council elections is the question of whether Labour will lose ground in 2010 or not. After all, these are the seats that were up in 2006, when Labour already had a really dreadful result.
If the local elections are on the same day as the General Election
probably - certainly being an independent in a Labour area (and there are a lot more of those than there used to be) up for re-election on a General Election day won't be much fun. In more general terms, again presuming that the local elections will be on the same day as the GE, we can probably expect Labour gains (though not large ones) in the so-called Mets and in the dodgy parts of London mostly because of increased turnout. Elsewhere... not so sure. 2006 wasn't
that bad.
There will be some weird results though - the London boroughs have never been up on the same day as a General Election and the (laughably named) Mets haven't since 1979. Ticket splitting in Birmingham in '79 was hilarious - probably won't be quite so funny with the Liberals no longer strong in the inner city, but there's potential for amusement in places.