I'll have to wait and see. I'm gonna be very disappointed if the only upgrades are internal. My iPhone 4 is fast enough as it is, I don't need a spec bump...and didn't wait 15 months just so I can upgrade to one.
At this point 4 inch screens are becoming a standard in smartphones...that's all I want.
I upgrade every year and only when the 3G came out, I realized I could live with the original iPhone and returned the 3G. I might be using this iPhone 4 for another year if that rumored new form factor isn't what they announce. But we'll see how convincing Apple is that I need a new phone, if it's the same exact design and screen size.
Another thing to add... When the 3GS came out, it was a similar situation..same form factor, with the 3GS getting a faster chip, video recording, and voice control. So with the S label slapped on there,I'm assuming they're doing the same this year with the 4S and the new voice control features to be introduced. I really hope they surprise us though.