It looks like AMD is planning on having 4 models of the Athlon 64 X2 when it is available, from the 4200+ to the 4800+.
The more interesting introductions are the dual Athlon 64s. There are four models: The 4200+, 4400+, 4600+ and, wait for it, the 4800+. These are 2.2GHz frequency processors with 2x512K cache for $537, and the same with 2x1MB for $581. A 2.4GHz CPU with 2×512 cache will set you back $803, and $1001 for 2x1MB. Is the $1001 just a random number, or is AMD playing numerical games? I vote games. Either way, they should be available starting in June.