I wouldn't write it off so easily, Forgie, I really wouldn't. Teams know their pitches down to single blades of grass and adapt styles of play to suit them. There was something unusual about Highbury's dimensions that suited Arsenal for instance.
Setting aside pitch sizes, teams tend to have better records at home anyway. Not to belittle Chelsea's achievement tonight, but they had 4 attempts on goal to Barca's 25 and 28% of the possession. At home. Now, I'm not suggesting that Chelsea did anything wrong, far from it - they played to their strengths and deserved their win. But when you are adopting a game plan where you expect to surrender so much possession and allow your opponents several times the number of attempts on goal you have, it's unlikely that it's going to get you a win over 2 legs. As we saw tonight, it can work over 1 leg -the home leg. Of course Mourinho managed it with Inter recently, so there is a precedent but still. Quite honestly I think only a fool would predict Chelsea to make the final, but if that happens I am ready to take to the stocks and hand you the rotten tomatoes myself.
I agree, Barcelona have a huge advantage in the second leg and I don't see Chelsea progressing further. However after tonights performance I think they're chances have increased to the point where it will be a tense, interesting match rather than target practice for Barcelona.