Even the clocks remained unchanged, so we are basically looking at GF106/108 and GF119 cores. The GT 635M is basically a GT 555M with a new sticker, the GT630 is the GT 540M, while the 520MX is now 610M.
The designations seem to indicate that Nvidia is leaving room for future 645 or 655 parts, probably based on new 28nm cores. There is still no word on any upcoming high-end models.