Another PS3 game that has gone up in value is Yakuza 3. But for the most part the market is pretty weak for the PS3. Even some of the better RPG's are still pretty cheap.
As far as what to release? I completed my PS3 collection more than a year ago. Since then I picked up the Chronicles of Riddick (has both games on the disc)... and that's about it. The only thing I haven't picked up is Way of the Samurai 4, which has a EU release in physical form. Still, it's typically $30 for a new copy shipped in the USA. Still, if they did the NA version on disc... for the same price... I'd probably seriously consider that... though I really need to play some of Way of the Samurai 3 to be 100% sure the series is for me.
Aren't both the PS3 & PS4 using the same disc(blu-ray)? I figured so long as Sony is producing PS4 titles, they can continue to offer PS3 ones as well. But I could be wrong in regards to the disc being the same, as I don't have a PS4 so not to familiar with things in regards to that system.
Not all BR's are the same. The base technoly is, but the disc encryption and the encoded barcodes and stuff are different. Plus they have a nice PS3 logo burned into them. From what I read, the discs are manufactured with some of the encryption actually in the form of defects unique to the disc. It's highly possible the discs are infact slightly different. I looked at a few discs last night for both systems and you can kind of see the defect in certain light and all the actual obvious differences around the center ring on the bottom. I'd imagine the blanks (even if they are unique) can be used on the same manufacturing platform as PS4 stuff.
The other thing beyond the discs are the BR disc boxes and box art. The PS3 boxes are somewhat unique in the BR world. The logo is pretty much inset and off to the top right corner of the front, the boxes are mostly clear for later released games, and the box art is cut down smaller than the PS4 boxes (and in line with BR movie art size). So art would require different paper, or more likely a separate cutting process than the PS4 art.
In the end they would likely need the PS3 specific blanks with the encoding on them, the ps3 specific br boxes, and then they would need to retool for the art or print it separately. I'd imagine the art is probably not that big a deal. They probably print that outside of the facility where actual product assembly is done, but the supply of blank PS3 discs and boxes is where a hiccup could happen which would result in new stock having to be created. IF Sony is sitting on a bunch of old stock though, then this may be a blessing to them. My guess is, if they have any old stock it's likely not enough for a full retail release.