Guys, first of all, remember that this movie is based on the original Superman movies, which show a pre-crisis Superman -- where Superman is the real person, Clark Kent is a secret identity in which he *acts* clumsy and dorky, and Jonathan Kent is dead. I wouldn't want to condemn Superman Returns because it shows a different interpretation of the myth -- I'm happy to accept its differences and appreciate it for what it is.
Also, Bryan Singer did say that this movie was "loosely based" on the first two movies, but was not intended to be a direct sequel. So the mind-wipe etc may not have happened in this universe. I think the aspects of this movie which can be linked with SMII are:
1. Lois and Superman having a romantic relationship, and
2. Superman's choices -- he chose Lois over the rest of the world in SMII, ended up regretting it, and in this movie he chooses the other way around (heading back to Metropolis during the earthquake.)
Also, the issue of him not being able to be with Lois unless he gave up his superpowers was from SMII. I'm glad that it's not the case in LnC and in the current version of the comics
And it may not be the case in this current movie series (because, we know, there *will* be sequels
)
I want to write more but this computer is painfully slow -- will be back later when I can find a faster one (at work!)