Earlier this year, AMD told the INQ that while it was possible for it to produce the chip using a 333MHz (or higher) bus, there was no commitment to so doing.
The information we saw lists the Athlon MP as the AMSN2800DUT4C, which pans out as 2133MHz/266MHz processor, running at 1.60V, and using the Barton core.
That may disappoint many, but AMD has to juggle the Athlon processors so they don't interfere too much with the Opterons up-and-coming. We suppose there's still time for AMD to change its mind, but it doesn't look likely right now. ยต
* UPDATE And yet, and yet. Over here, there seems to be a 2800 AMD MP chip sold with a 333MHz front side bus at $329...
See Also
Opteron SKUs go to 2000MHz