Will all due respect, there really hasnt been another contender to rival that of the Hulk PF - possibly the upcoming Planet Hulk? But for me personally, until they release another comic Hulk PF or LSF then i cant see the market value of the original Hulk PF being affected that much
With the Captain America PF, well there is a new kid on the block so to speak with the reveal at this years Con of the new Cap PF. Some will say they prefer the new dynamic pose to the original...for me personally, i can see the market value of the original Captain PF decreasing once the new one is released.
The Thor PF, well...again, like the Hulk PF, there really hasnt been a rival as such to contend with the original so the value of the original PF i think will stay as is
As for the Spidey PF, i would say in the last year or so that the Comiquette has actually overtaken the PF in terms of market value. I dont see the Spidey PF as being that desirable any more for collectors (unless its literally the limited edition versions!) I have both the PF and Com EX's and unless i can get the Green Goblin PF within the next few months or so, i can see myself parting with my Spidey PF