It gave me an all Dutch interface.... But I don't like Dutch program interfaces... and I couldn't change it.
There isn't an ad-block feature.
But above all: I don't trust google that much. As someone said on /.: "Would you use a browser produced by Doubleclick?". Google's crown jewels are the information about what people do on the internet. Sure, the browser is open source, but I don't like a browser which is one step away from giving out whatever I do to a company which will keep it around for how long no-one knows. The EULA shows this. They altered it, but trust me: they didn't 'accidently' kept that clause they now removed in there.
So I won't give up firefox 3.
44 extensions? I have 3 or so, tab mix plus, adblock and delicious.