This is rather evolution than a revolution, just slightly faster and that’s it. The faster one, Radeon X1950XTX is set to replace the current-fastest ATI Radeon X1900 XTX while the new Radeon X1950XT aims to replace X1900XT cards. We still don’t know about the clock speeds but we know that the new cards comes with GDDR 4 memory. They are set to be released at some point in September/October timeframe.
With such a small leap, it doesn’t seem worth it to get excited. Although, it will be interesting to see how it lines up price wise compared to the obviously faster 7950GX2.