Oops!
I think I once read the PS3 AV multi out is the same as the PS2 AV multi out. So, I would be able to use my current PS2 AV multi out component cable. I hope this is true. It means one less thing to buy.
I don't think it will come with a multi connection AV cable. If a differnt AV cable is needed other than composite, you have the option to buy a different one like you have now. I think it will come with a standard AV multi out cable in composite, and one HDMI cable. Hmmm, now that I think about it, I doubt they'll supply a HDMI cable. Not that many peopld have a set with HDMI since it's so new. Plus, I'm sure they can afford to buy a HDMI cable on their own.
DVI is dead and not that many HDTV sets had it in the first place. HDMI came out to replace it nine months later. But, those with DVI inputs on their HDTV sets can still use the HDMI outputs on the PS3. There are adapters to go from HDMI to DVI. But, it wont pass the digital audio signals. You would need to use the optical out for the digital audio. DVI is digital video only. There should be no loss of video quality making the connection this way, so no need to worry.