I realize this is a common problem even in the current iOS 7 versions but I've never ran into this issue until going to Beta 1 and now Beta 2. I have iMessage set up with my iCloud e-mail and my phone number, the settings say start new messages from my number but 90% of my messages are going from my iCloud E-mail. It's mostly just an annoyance to those who are receiving messages from me, but I was curious if anyone else was experiencing this with the betas.