I bought it and seems to work great.
Unfortunately Garmin themselves do not have much info however I had to try it.
I have an Unlocked Rogers BB Bold 9000r being used with FIDO (their other company) using BB Connect. I am in Canada so it does have all the North American Maps. Garmin was telling me that it only worked in the US. It is not carrier specific and the best way to buy is through Handago using the 8310 software Handago has not updated their site yet. Garmin does confirm it works with the bold.
Garmin also indicated that they are using newer maps. Now.