Actually, I have found over the past couple of years tap water gives me major heartburn if I have more than say, half a glass. I have also noticed that the chlorine smell has gotten stronger (I don't know if they are actually adding MORE chlorine or not).
I have been meaning to pick up a brita just never remember when I'm in the store because whenever I'm at someone's house who has one, I don't get any reaction to tap water once it's put through the brita.
Also, yeah, CHANGE the damn filter. IF you don't believe us, open one up and see the crap that's in it.....