I can recall the first two from memory. I barely read The Register.Since this is rather old information i would suggest you start looking at the archives of The Inquirer, Anandtech, The Register, or any other web computer related news source.
The Inquirer is gong to show release dates for G84/G86 from late 2006. Ho hum until early 2007.
Anandtech is going to pit the 8600GT vs. the 7600GT. Given the time and launch price they're going to recommend the 7600GT because the 8600GT barely offered any performance gain. We're talking ~$100 cards vs. the usually $150 8600GT at the time. The 7600GT is going to win in F.E.A.R and 3DMark 05. The only thing that held back the 7600GT at the time was the 128-bit memory interface.
Once time goes by the 8600GT's architecture is going to pull ahead in 3DMark 06 and in games.
The 8600GT is a completely different architecture like I've said before. It's unified shader hardware over the fixed vertex and pixel shader ones that existed before. You're also going to get DirectX 10 support with unified shader based cards.
Please show me where the 8600GT is somehow a rebranded or higher clocked 7600GT.