I do not agree with the statement that "as long as Rachel is around, there's no Jean" because Jean and Rachel both existed at the same time for quite some time. They never interacted as much until the latter part, but still existed. Also, as far as storylines go, Grey's End would not have even occurred if Jean were alive. That story is specific to Rachel because it compounds the whole idea that she is alone and the future from whence she came is that much closer to coming to pass. I do not view that as a Jean storyline at all.

As far as the shadow form thing and phoenix eye thing, well, I'm not so sure where they are going with that. I may be wrong, but I do not believe Jean ever manifested that in the real world, only the astral plane during the Revolution storyline. In Morrison's run, that was never mentioned, used again. I'm curious as to see where that is going, hopefully somewhere logical, as logical as you can get in Uncanny. I'm not sure where these plot-threads that people keep mentioning are. If she were taking Jean's place she would be the resident telepath, but that role has been filled by Emma Frost who is now the head mistress as Jean once was.

I can see an obvious difference between the two and see the relatiionship, but I don't feel that one replaces the other. However, everyone is welcome to their own opinions, but to me it's only a book and I do not lose sleep over it.