This is a little confusing for me, it does seem that Marsden will play a decent sized part in Superman Returns, and be sort of a human counterpoint to Superman, but when were the blogs filmed? Do we know for sure?
Also, the alleged fan sighting saying that Jimmy and Famke are hanging out could mean he really is balancing his schedule between the two, or he could just be goofing with his friends Famke and Bryan on a day where he doesn't have to work.
We know that most of his stuff has been wrapped up, this leads me to believe that most of his scenes will be with Jean as we have heard hardly a peep from her aswell.
I'm speculating that , 'most' of his stuff being done means that he may still have to film for some ensemble action at the films climax, having the emotional and minor action scenes with the other characters already wrapped up.
I suspect that Storm and Wolverine will be elevated to Xavier's aides in this film (judging by the HNR pic) which means Cyclops doesn't necessarily have to fulful that role, I suspect he will be 'key' to a few scenes involving Phoenix and the X-Men, but not necessarily Magneto, Worthington, Bill Duke, Moira, Kavita, the Brotherhood.
You have to take into account that ALOT is going into this movie, there are ALOT of characters and plotlines being interwoven into a narrative, this does not mean that Cyclops won't get alot of screentime, it just means that, given the production schedule of the film, time economy is essential. So they will try and wrap up all the scenes where certain characters are involved in certain places and certain times.
Maybe Ratner wanted to wrap up all the Cyclops, phoenix, etc etc heavy stuff early on as there was a lot of SFX and editing to go with those scenes, not because they were killing the character.
We really don't have enough information at this point, there could be a number of things going on. Early script drafts, rumours and conjecture about inter-studio politics and schedulings can give you a speculative information to work with, but when it comes down to it, it is incredibly flimsly information to base an assertion on.
(I know it's your opinion, but it is always best to try and see a rounded perspective first)