No it is NOT worth it, 1 and a half gig for 20-30 minutes of gameplay, if that!
I'll start right out by saying how hopelessly subjective and biased I am because of my love of Oblivion and the Elder Scrolls series over Might and Magic. With that in mind I still thought I'd give it a go because I enjoy fantasy RPGs and quite liked the look of the preview videos.
The graphics pale in comparison to the powerful engines behind Oblivion, but the first 'proper' level you get to play has some pretty visual effects and well constructed models/materials. Its obviously source and shows its age because of this (a lot of harsh angles/world brushwork), but its far from an ugly game. Could've done with a flashlight though, that bluevision is pants
The feel of the game takes some getting used to, not only can you see your character but the head bob is very significant, with the display moving all over the place in combat and even while turning. Combat is interesting, but doesn't feel fluid, you dont get the real 'clang' of swords and shields in Oblivion and the feeling you are putting power into attacks.
Other misc problems: the UI is a little messy, especially the binding/startup menu system, black on black? What were they thinking? The characters foot also seems to extend about 3 feet further forward than it looks :S
Maybe I just need to play it more to appreciate it, I wasn't that impressed though.