The next CPU introduction will mark the Athlons entry into the low-cost market with the Spitfire. The Spitfire will be available only in the 426-pin Socket-A form factor and will feature a smaller on-die L2 cache than the Thunderbird (most likely 256KB). Other than that key difference (and cost), the Spitfire will remain identical to the 0.18-micron Thunderbird.
In the second half of 2000 we will see the introduction of the Mustang. The Mustang will feature, according to AMD, some "mobile features" which will most likely include the Gemini technology discussed above. It will feature a full speed on-die L2 cache of up to 2MB in size, making the CPU ideal for high end workstations and servers. It will be available in both a Slot-A and a Socket-A format and is still based on the 0.18-micron core, that will be introduced later this year. AMD also made it a point to mention that the CPU will feature an "Enhanced Core" but we are not certain about the specifics of those "enhancements."
A "value" Mustang will be available, only in a Socket-A format, and it will most likely have a smaller L2 cache than the high end version.
AMD briefly mentioned the SledgeHammer CPU which is their upcoming x86-64 CPU. There wasnt much that they were willing to disclose, but the data we were given is summarized in the slide below: