So, any 80gb will do fine ? My AVR is hdmi 1.3 (onkyo 805).
Thanks Dave
Be warned, Sony has recently released a new 80gb PS3 model that is essentially the old 40gb model with a bigger hard drive. It is priced at $399 MSRP and does not support SACD (nor can it play PS2 games, though I don't think you're concerned about that). As $399 was also the price of the 40gb model, it's likely that the 40gb model is going to be phased out.
Confusingly, Sony is apparently going to release an 120gb model in October that is also a clone of the 40gb model (i.e. no PS2 or SACD compatibility).
You want the "old" 80gb model, which you will likely find bundled with Metal Gear Solid 4 and priced at $599 MSRP. If you search for "Playstation 3" on Circuitcity.com, for example, you'll see they carry both 80gb versions of the system right now.
An old 20gb or 60gb model would also do, but you'd have to find that second-hand as those versions are long discontinued.
Wikipedia actually has a nice summary of the myriad of different PS3 models Sony has put out. It's under "Retail Configurations" in their PS3 article.
On the plus side, the PS3 really is a great blu-ray player and a very good standard DVD upscaler. Just make sure you do all the updates, whichever model you buy. Hope that helps.