so I guess it doesnt take a second core revision to unlock all the SP's on die?
No, it's not needed.
Seing how good GF104 is in comparison, if Nvidia has another chip in their sleeves that's going to be a "GF104"-like GPU with 3 clusters instead of 2. IMO that would definately compete and even beat a Southern Islands all while being smaller than GF100 so they would be in a better situation than now (GF100 has 3.1 billion transistors, GF104 has 1.9, so 1.9 + 50% will always be less than GF100). But IMO they could even aim a little bit higher and take a "minor" risk and release a real monster. That mosnter would be the aforementioned 3 cluster "GF104-like" chip but instead of 48 SP (3x16) per SM, it would have 4x16= 64 SP.
Architecturally it makes all the sense: GF104 is superscalar with 2 warps schedulers, but only 3 SIMD execution units. That doesn't make a lot of sense, since in one clock cycle it can issue two warps, but on the next only one can be issued, hence the move to 4 SIMD units is unnavoidable. Now, regarding the die size of such a chip, if you compare GF104 and GF100 it's clear that adding the extra 16 SPs into the SM did not increase transistor budget a lot, considering they also doubled SFUs and TMUs on GF104. GF104 is way more than 75% of a GF100, but has 60% the transistor count and die area. IMO Nvidia
might be in a position right now to release that chip consisting of 3.2-3.4 billion transistors and around 560 mm^2 die area at 40nm (not the biggest chip Nvidia has ever done). It would be a risk, yeah, again yeah, but a risk that may very well pay off, we are talking about a chip not much bigger than GF100 but with 768 SPs! But that's where the Fermi architecture was created to go and beyond that. Next on 28nm, who knows, it could be 4 clusters with maybe 96 SPs (6x16) per SM and 6 SMs per cluster for a total of 2304 SPs!! (Impossible? R600 started off with 320, Cypress has 1600, SI will have how many?)
Nevermind just a little bit of speculation...
As of GF104: It's taking them too long to unlock them tbh. I've been wondering lately, if they are not into price fixing practices again (Ati and Nvidia). AMD doesn't lower prices, Nvidia does not want to be aggresive with GF104, it makes me wonder, really.
The excuse with GF104 has been "improving yields" (although those excuses come from the rumor mill), but no one with a brain believes that. OC potential is so vast that there's never been a valid excuse for not releasing the card at 750-800 Mhz stock. And if clocks are so good there's no way they cannot get 25%-40% of the dies with full 384 SPs and 800 Mhz capable, which is what they would need to create an SKU capable of beating GTX470/HD5870.
I'm liking the heatsink design.
Almost makes my cards heatsink look tiny! 
