There are many flaws, but overall, Assassin's Creed: Bloodlines is pretty fun.
*Almost all the elements of AC from the console games are here
*Combat is pretty fun, although enemies take too long to attack
*Counter/Combo/Stealth Kills are satisfying
*Hidden Templar coins for those who want some more replay value
*Climbing buildings is fun
*Sound effects are nice, though repetitive
*Great graphics(Altair is very detailed)
*Unlockable content from AC2 PS3
CONS:
*very easy
*voice acting is mediocre
*empty, lifeless cities with a draw distance that is acceptable on a psp, but still disappointing
*short, 6 hour story
*achievements have no reward system
*Cutscenes are rendered in-game, so they don't look particularly good, especially when the camera zooms in on a low-res face
*Free running is jerky, and the controls are occasionally unresponsive
*Story is boring
*Lots of glitches
*Stupid AI
Yes, I listed more cons than pros, but these are easy to forgive. It's probably because I am a big Assassin's Creed fan, but I just found this game to be entertaining. The story is short but you can replay all of your favorite missions. The free roaming, while limited, is still pretty impressive considering that you are playing it on a psp.
If you are a fan of Assassin's Creed, you should get this game. If you aren't, you probably shouldn't.