I took a short look at the file, par curiosité. Here is a little hacky ugly little piece of software that is able to split this dumped update file into subfiles. There is an obvious index at the beginning. This most probably looks like a custom SONY archive tar-like file format (PBP? this is in the first 4 bytes)
http://www.nobis-crew.org/split-update.c
First file == a PSF file, looks like directory entries or something, but it's the same format as the PARAM.SF0 in the IGN's file.
Second file == a PNG file, as previously dumped
Third file == "PSMF0012", seems to be the same format as the IGN's ICON1.PMF file.
Fourth file == another PNG
Fifth file == PNG
Sixth file == WAV file, as the IGN's SND0.AT3 file.
Seventh file == Aaaaah, now this is interesting. It says in the header "PSP updater". Ho, great :) Nothing like this in IGN's. Rest looks compressed or crypted.
Heighth file == PSAR file (AR as in ARchive?), nothing like this in IGN's. Rest looks compressed or crypted.
So, this PBP looks like it's containing subfiles, first beeing some files from a savegame, and the two last beeing "something" (but remember we didn't get any "data" as in "no savegame data"). So, we have three options now:
-) It's a fake thingy built by somebody quite good.
-) It's a real savegame, with the two last files beeing the 'data' of the game, shipped as a "bundle". Only problem is: where are the filenames? I mean, if it's a SONY compressed "savegame", it would need directories and filenames. There are none here.
-) It's a real update file, with sony having some dummy savegame data before, either by mistake, or with the intention to mess up with our minds. Or maybe the update has to go thru the "savegame" system to work. No idea.
Sooo, that's all for today; I've got lots of other things to do :) Somebody would need to try some heuristic method to uncompress the two last files, but I'd bet my two cents that this is crypted (remember the RSA logo somewhere beneath the PSP?). Just as a hint, these two files compress VERY badly (even with dictionnary algo such as bzip2). Which means that there is a huge entropy in the bytes distribution.
Have a nice day ;)
pixel: A mischievous magical spirit associated with screen displays. The computer industry has frequently borrowed from mythology. Witness the sprites in computer graphics, the demons in artificial intelligence and the trolls in the marketing department.