Still 5 bars n most places. The only place where it is different is in my apartment. With my 3g I could barely hold a conversation because it would either drop the call or the quality was so poor. With my ip4 I used to get 4 bars here with 4.0, now I get 2 (occasionally 1) but I haven't dropped a call yet.
I don't care about bars honestly. I used to drop a call on average at least once a day with my 3g and I haven't yet with my 4.