Thanks for the link; I guess that explains why, as someone who likes to be in control of my technology rather than the other way around, I did not buy into either iPhone or BB myself.
But my daughter wants Blackberry Messenger (which as far as I can tell is proprietary, and thus Blackberry's one main killer app) so that's what we need to get. I assume the semi-mandatory Blackberry data plan (why do they feel simple TCP/IP is not suitable for their users I wonder?) is included in the data allowance provided as part of Blackberry tariffs, yes? And that when she's at home, our home wi-fi will automatically be used by the phone for all data traffic, in preference to using the 3G cell connection?
The reason I believed we needed OS 7.1 is, as I understand it, that it's required in order to be able to use a Blackberry phone as a wi-fi hotspot (so her 3G data allowance can occasionally be shared to allow her to use her wi-fi tablet while out and about). Again, at home the tablet automatically logs into our home wi-fi anyway, so wi-fi tethered data usage won't be massive.
Am I correct in the above assumptions? And also that the 9300 cannot handle OS 7.x at all, and thus I'll need to get her a 9360? If the 9300 is sufficient she's actually more than happy to go with that - mainly because it comes in a wider variety of colours! ;)
[Edit] One other quick question (sorry!) - as UK customers, when roaming in the USA obviously we'll turn all cellular data OFF for the duration, but we will have wi-fi access at the hotel and at other times; I assume that everything on the phone will work normally for her in that situation (BBM, apps, POP3/SMTP email, etc)? And texts/picture messages while roaming should go via GRPS so they won't need to use a normal data connection.