Hey I have the data plan with Verizon wireless and i'm just wondering if using yahoo messenger costs me money to use? My second question is for someone else but if they send a text message to an email address does it still count as a text message or will it count as data? Thanks everyone!

Nope....if you use IM programs with the Blackberry (either the Blackberry Yahoo IM or Google Talk program, or even Jive Talk for AOL, Windows Messenger, etc.) it all counts as data, so if you have the unlimited data, you're golden. It doesn't count as text messages as the Verizon IM programs through their "regular" phones do. If you send a SMS or MMS, it counts as a text/pix message and not data. So it would be covered under whatever text/pix/flix plan you have.

That is a huge plus going with the BB rather than the Voyager, unless you have the select or premium voice plan that gives you unlimited text.

Just in case for whatever reason you didn't pick up the answer to the second question, it DOES count as a SMS even if you are sending to an email address. If someone sends an SMS to your email that you retrieve via BB data then you are not going to be charged an incoming text.

Neat bit of info: with OEM AIM you can send data instant messages to phone numbers, which they'll recieve as a text. If for whatever reason you have unlimited data and not too many SMS to burn.

Wow that's great info, thanks guys!
When I go to the verizon download page on my blackberry and try to get AIM it says my blackberry is unsupported = . Is there another version that works?

You can try JiveTalk. It works with AIM, Windows Messenger, and IRC, as well as Yahoo and GTalk. You can try it free for 30 days, and then it costs $20 ($30 if you want the ability to move the application in a new BBerry if you change your handset).

Yea, get JiveTalk. AIM on the BB is pitiful, buggy and mostly demonic.

Free trial, then $20 or $30 according to what you buy.
beejive :: JiveTalk mobile messaging

Oh, so there are no free solutions?

You can try IM+ but nothing comes close to JiveTalk. In my opinion it is worth every penny.

Here's a whole list of IM apps. You get what you for...
Instant Messaging FAQ - BlackBerryFAQ

good luck.