I have been an Apple devotee for nearly 10 years so when my old, old, old PowerBook G4 died there were very few products I was willing to consider. Despite the (comparatively) hefty price tag I opted for this 24" iMac and I have to say my decision has been justified a million times over.
I work as a video editor so I really require three things: Raw processing power, excellent graphics rendering and exciting software to run. With this mac I get all this and more. The mac runs Final Cut Studio like a dream, and I am yet, in 6 months, to have a single problem from either lack of speed or lack of graphics quality.
From more of a consumers point of view this computer rules again. Whether it's listening to music (iTunes, good as ever, or Front Row, excellent for use as a media hub), watching films (Great picture and sound quality from DVDs or iTunes store rentals), messing about with pictures (iPhoto might be all you ever need) or just browsing the web (safari is exceptionally quick) this computer is a dream.
I couldn't genuinely recommend this to someone who isn't a pro-sumer, someone with a skill that the mac would be a great use for (editing, photoshop, mixing, producing music) because of the price tag, but if you want and/or need a computer that considerably outplays a similar speed computer then you absolutely must consider this!
Oh, and it's a very beautiful thing to sit on your desk. It's just about the only piece of art i've got!