Brown has gotten on my nerves at times this year; I don't know exactly why. I think it's probably the previously mentioned obligatory and sometimes-forced guffaws at JD's comments. I do agree that Deshaies is top-notch, though, and I think Brown is good too but I don't really watch enough baseball besides the Astros to have much to compare him with.
I have been listening to the non-Milo radio guys a lot of late and, though I can't say I was overly impressed last year, they have grown on me. They're quite funny in a subtle way and the more you listen to them, them more you catch and appreciate that.
I do listen to lots of baseball over the Internet (GameDay Audio is so awesome that I've been waiting for years for MLB to screw it up somehow). The west-coast NL teams' (LA, SD, SF) broadcasters are all pretty good IMHO--Scully, the Morgan-less Jon Miller, et al. ensure I waste lots of hours at the PC when they are playing at home.