Apple announced a new imac line today at a press conference, all featuring the hd 2400/2600 chips. That's a pretty significant oem win I guess.
Edit: Just a comment that it seems like ATI is getting back some of the low to mid range GPU business they lost during Nvidia's 6600/7600 era. Even the within htpc crowd at avsforum, the 2400/2600 are getting the kind of attention that the x1300/1600 never got.
I ass-ume the sole reason is that they're dirt cheap since noone wants them.