The 30 dollar data plan you added to your plan for your Blackberry will include unlimited instant messaging. SMS and MMS text messaging is different and not part of the 30 dollar package. So instant message all you want.
I got this information from Verizon Wireless' website:
Instant Messages are charged just like Text Messages so you can use your Messaging package monthly allowance or 'pay as you go' for 20¢ per message. Instant Messages are not included as Mobile to Mobile messages in any bundle that includes Unlimited Mobile to Mobile Messaging.
Whoa people. Calm down. All Blackberry Instant Messaging and Yahoo, MSN and AIM is included in the data plan for Blackberry. That information the original poster found is only for Mobile IM, which is not a Blackberry application. It only applies to feature phones. Blackberry and other smartphones don't use the Mobile IM platform, they have their own standalone IM applications.
So let's all punch ourselves in the face and move on.
Thanks for clarifying. My husband wanted to get a BB so we could "chat" for free instead of eating up our text messaging minutes. But he had found this information and thought it would be better to just bump up our text plan instead. If this is the case, then we will just get him a BB and chat away