Probably a stupid question and one that has been asked on here many many times before but I am new so hopefully someone can help me out. I got the 8310 for the good keyboard for texting and for me eventually getting a plan for it. If I do not pay for a data plan right now will I be charged more per month? I have a plan through AT&T and have unlimited text and picture messaging. How much is a data plan a month? Thank you for all your help.

in order to use the BB to its full potential I would say a data plan is atleast in order. If you want unlimited depends on how much you use it.
If you just recieve an email (and little to none internet browsing) a day and your BIS plan includes 5mb free traffic a month then its more than good enough for you.
If your not going to have push email and is just going to use the BB as a phone with sms possibility you can stay with your current plan.
However, MMS messages require a data plan (if i'm not completley misstaken).

I'm not to familiar with US carrier prices, hopefully someone else can answer that.

you're already paying extra...just by being with AT&T

j/k

not sure about AT&T's data plans since im not with them, but if im not mistaken, its $35 for unlimited data without tethering. Check their website to make sure. They should have plans listed accordingly, but check data plans made specifically for blackberry ONLY.

Cell Phones and cell phone plans - Wireless from AT&T, formerly Cingular

take note that it should be a BlackBerry data plan and not just any ordinary data plan for your emails to get pushed to your device

Some prefer to pay a little more for real coverage!