580 HP, underrrated by factory really around 600 to respect the 650 hp Vette, anything else is not going to beat the M5 or E55 they are supposedly targeting to beat. Not to worry about 580 HP Audi RS6, that car will probably weigh in north of 4500!
The reason why I stated my guess to be 525-530 HP/500-505 TQ is because I believe GM will use a factory supercharged LS3 (without forced induction is rated at 430 HP). Add a nice supercharger and a fairly conservative stock tune and you get another 100 horses out of the motor, which could easily be increased with a pulley swap or more aggressive tune.
If I were to hazard a guess (totally to be taken with a grain of salt as I have absolutely no inside info to back this up) for the sake of interesting discussion/speculation I would say that the price point will probably be around $60,000 fully loaded. I believe GM will try to stay somewhat close to what the previous generation's price point was (about $6,000-$7,000 increase from previous). This would also be supported by the fact that superchargers for our current cars are about $6,000 and they add between 100-130 horses. That is exactly how much HP they would be adding to the stock LS3.
On the other hand, GM could be figuring that since the CTS-V is a relatively low-selling, limited-production run, car they may just add gobs of HP and also up the price at an equivalent rate. Maybe 550-600 HP @ $65,000. I hope this is not the case, because that makes the car just a little more out of reach for us young guys who are still trying to make the big bucks. I believe that the possibility to achieve much more HP will be there even if the engine stock, has a MERE 500 horsepower, haha.
But, back to the original statement. I think GM is trying to selling a lot more of these cars than the previous generation, hence most likely making an automatic available as stock, and a 6 MT as an option. Therefore, my original engine/price guess still stands. Damn, I hope I am right after all this...
I agree with you on the price point lets hope it's not to far up the scale. But as far as a supercharger adding only 100 hp, thats an aftermarket SC added to an NA engine that has a very high compression ratio. The LSA on the 09 CTS-V is an engine designed for a supercharger. Even the blown Northstar goes from a stock 320 HP to 469 in the STS-V. Thats why I believe they should be able to get at least 550-580 from the upcoming LSA, without costing so much.