It's not rumoured, it's true.
I think I'll skip on this one. I have a GBA (no SP) as well as a GB&C, and a Gameboy Player, not to mention a DS. And I really don't think it would be comfortable for me (or, for that matter, most of us) while holding it. Judging by the size, I would have to hold it with my fingertips, and I have pretty big hands, so it would probably be even worse. As it is when I played my friends SP, it was tough to hold comfortably. And then the price is another deterrant - $120 over here is just too much when I have a multitude of options to play my Gameboy games.
Are any of you considering getting one, even after the price has been announced?