A friend of mine just sent me an email asking if I had a 'Profile' option which he noticed had popped up in Settings -> General since updating to v2.1.
When opening the 'Profile' menu it simply states 'Beta testing verified'.
if you install certificates, like for an Exchange account etc., it saves them as a profile. it's also used for devs i think, but i don't know in what capacity.
I think it's a list of trusted Certificate Authorities (CA) (or just a list of trusted certificates). For example, if you have a corporate VPN connection set up, you'll get a profile installed for it.
A few other non-Developers have seen this. It's strange as the provisioning profile is assigned to Apple and is simply called Beta. It probably shouldn't be there. It's almost like they forgot to remove it when the promoted the last beta firmware to the production version. It's not doing any harm, but I expect Apple might well sort it out in the 2.1.1 release...