The Athlon 700 was the last Athlon to feature the 1/2 speed L2 cache and it will most likely be a fairly expensive part to pick up even after the 750 and 800MHz parts make their way into the retail channels. The Athlon 800 is just another step in the Athlon line, for AMD, it's purpose is to offer a clock speed competitor to Intel's Pentium III 800, but it's main purpose for most of you will be to drive the prices of the other Athlon processors down which is never a bad thing.
The Athlon 800 will make its official shipping introduction sometime in January, hopefully by then the Athlon 750 will begin to surface around the net as well. It won't be much longer until we begin to hear more about AMD's Thunderbird and Spitfire based Athlon processors featuring a likely 512KB of full speed on-die L2 cache, until then, if you are in the market for an Athlon, the 500 - 600MHz chips are pretty affordable and very high performing solutions. If you must have the best then there will always be the 800, but be warned, the performance gain going from 700 to 800 isn't as great as we'd hope it would be courtesy of the 2/5 L2 cache divider.
All of this makes you wonder, who will be the first to break 800MHz?
For more information on the Athlon 800 take a look at Sharky Extreme's review of the CPU.