I saw both
The Prestige and
The Illusionist this past weekend -- with two reviews of the former scheduled for the website, I made a point of seeing it Friday evening, and then circumstances invited seeing the latter on Saturday.
The Illusionist has been out for a month or so, and I'd considered assigning reviews of it, but timing with the reviewers didn't work out and I wasn't sure it was even relevant for a website focused on SF and fantasy.
Both films are worth seeing, though I think
The Illusionist is probably better seen first, since it's a rather simpler, more straightforward, more linear-plotted story about a magician/illusionist than the far more complex
Prestige. As for the relevance of
The Illusionist to SF/F, I wouldn't want to spoil anything, but I will say that it would be rather difficult to review, especially in the way it presents magical tricks or illusions (i.e. it uses FX), without revealing whether or not it 'really' is fantasy.
I see from comments trickling in to my HP Lovecraft posts that I need to address the topic once again, in terms of 'reviewing' the stories, saying what I personally think about them according to my own reviewing standards. I will do so, though in the context of what kind of sense it makes to 'review' works that are already part of a literary 'canon'...