I have played with both. Pearl flip is really a glorified cellphone not a blackberry. My wife has a curve and LOVES IT! A friend of mine, his wife has the non-flip pearl and HATES IT! Curve does not have 3g...not sure if the pearl does either. But she (wife) always has signal, has no problem with apps or anything. Depends on what you like. If you like cramped phones go with the pearl, if not then go with the curve. Your best chance of figuring out what really works best for you, is to head on down to the verizon store and play with the phones.
*sorry if i sound harsh, no intention of coming across that way* *Cheers*
Actually the Curve 8330 and Pearl 8130 both have Rev. 0 which is for the EVDO network. EVDO is considered Verizon's (Sprint/Alltel) 3G network. So yes, both devices have 3G. Rev 0 speeds are really comparable to DSL speeds; 400-700 kbp/s. Rev A speeds, which the Pearl Flip 8230, Tour 9630 and Storm 9530 have, are about 700kbp/s to 1.4 Mbp/s.
Really decent speeds for wireless broadband.
I don't have experience with the Flip Pearl per se, but I do have experience with the original pearl and the curve. If you are looking for a blackberry you want the curve. The pearl, although great, is a scaled down mini verision of a blackberry. I enjoyed the pearl but it was very cramped and I found it difficult at times. the screen is tiny so web browsing was not enjoyable. The curve on the other hand has a nice feel and web browsing is good. If you're looking for a true web browsing experience I'd recommend the storm which is what I have now.
Some additional info