Aston Virage won't be that collectible in the long run. Astons look nice but don't have pure cachet nor great resale (amongst modern models), and the Virage was a pretty humdrum model considering it was just a variation on the DB9. Koenigsegg, just a nameless hypercar, no historical pedigree. Spyker, about the same, unfortunately (love Spykers, though). Zonda, somewhat better with the pedigree considering it's been around for about 15 years, but hard to say.
The Reventon looked like it was gonna be one of those keeper cars, but then they released the Aventador plus all the matte paint options and the Reventon suddenly seemed worthless. It might have more value much, much later down the road.
If you think back on all the old classics from the 60's and 70's from makers that went defunct - DeTomaso, Jensen, etc - those are all cool sports cars and many were good too, but never really went god tier, because they didn't have a historical pedigree before that, and then went defunct right after.
Ford GT40, definitely a keeper. Probably won't be another American car made like that again, except for this new Viper. The new Viper might hold it's retail value forever, who knows. At least as long as gas stays under $10/gallon.
There's a used 599GTO for sale on yahoo Japan. It's selling for about what the retail was, so that means it's not going to get the double-price Enzo treatment either.