Well, blackberries are fine for calling and their email is top notch obviously. I like their texting system very much too, it's almost like IMing people. I find the calender function to be very lacking, it would be nice if it were possible to display the day's events on the home screen or something. In fact, I think the calender on my old nokia n85 was better. I don't check the weather that much but I imagine there isn't much room for RIM to mess it up too bad. Note taking and calculator is pretty standard. Music is rather poor, but if you're going to be listening in the gym it shouldn't be too bad. The 8520 does have dedicated audio buttons (skip and play/pause + volume rocker) The only downside would be internet browsing. It's not horrendous, if you just want to look something up it's alright. Don't expect to be browsing for fun though. I've never tried 3g browsing btw, only wifi. The camera on the 8520 sucks, the 9700 is much better but it's not gerat. Battery life on blackberries is excellent, I can use mine for almost 4 days on a single charge.
If you're looking into HTC/Samsung/Android phones, the huge brick phones seem to be quite popular now. The HD2, Droidx, evo 4g (which I just got today) are all gigantic monsters. I personally didn't like hd2 that much, I felt that the screen was too sensitive and a lot of times when I was trying to scroll through a menu I would end up clicking an icon instead. evo 4g screen was excellent, very responsive and easy to use. I don't have a droid X but I played with my friend's briefly and it's nice. All of these phones are great for videos and internet browsing is very good too. Typing is ok once you get used to it, but I still prefer phones with keyboards. Many of these phones also have a swype function which you may like once you get used to it. The calender function on these phones is much better than on the blackberry, and they definitely have a lot more capabilities. Music is alright too, I'd say it's better than the blackberry but they won't be replacing my mp3 player. Battery life on these phones is rather lacking. The droid X doesn't even last a full day, it dies in the afternoon.
I liked the HTC aria very much. In fact, if I didn't absolutely have to have UMA I'd be using it right now. The build quality is superb and it's an extremely compact phone with all the android functions. If you just want a phone with phone and work functions, a blackberry would be great in my opinion. The speed isn't really slow, it's actually quite snappy when it comes to opening menus and stuff, in fact I was very impressed with the picture viewer. There's practically zero lag when opening/switching pictures. The only thing that's slow is the internet browser. I hear that the opera browser for bb's is better, but the stock one is pretty lacking. If you want a fun phone that you can get apps on you're definitely going to want android or some similar touch screen phone. The screens on these brick phones is just ridiculous, I feel that if I could hook my 360 up to one I could almost play games on them. They're awesome for videos, pictures, and stuff. My friend trades stocks on his 3g network and it's fast enough for him. I don't have any experience with 3g because I can't pay 100$ a month for service. I don't know what Epocrates is, so I can't help you there.