They'll definitely come 3rd in the Premier League, but I don't think that will be very difficult next season. But that isn't winning something, that's being the third best team in the Premier League. They might win the Carling Cup or FA Cup if they take them seriously again, but they will be a close run thing between the top 6~ Premier League teams as well. These competitions always depend on fixtures and what else you are challenging for.
Chelsea will probably sell / release Drogba, Kalou, Malouda, Bosingwa, Ferreira and maybe their reserve keepers overall. Possibly a couple more but I think Chelsea's squad will look a little bit like this:
GK: Cech, Turnbull, Hilario
DF: Ivanovic, Terry, Cahill, Cole, Luiz, Bertrand
MF: Lampard, Essien, Meireles, Ramires, Mikel, Romeu, McEachran, Mata
FW: Torres, Sturridge, Lukaku, Hazard, Marin
I would say that both reserve keepers for Chelsea are not good enough, so bringing in another would be a priority for me if I was at Chelsea. If Bosingwa goes, along with Ferreira, they need a new Right Back. They could probably do with additional cover too. Malouda also might stay.
I can't see them doing much else unless they force out some of the old guard.
Cech
Ivanovic Cahill Terry Cole
Mikel Lampard
Marin Hazard Mata
Torres
If we assume that is something like Chelsea's usual starting 11 (RB, CM, RF are pretty much up for a challenge for a place) then it quickly turns into the team that finished 6th last season and manages to hold onto some cup success that won't happen in the same way again. They don't even have their manager yet so I can't see how a real plan is in place. Quick change usually doesn't work and they're going to have to do so much of it very quickly. I don't fancy Chelsea to do much other than settle into the top four again.