Although I'm not really a collector of game boxes (anymore), I was quite impressed by the Collector's Edition at first: I still like the artwork a lot and the items are cute (especially the pin). With the booklet (presumably based on the ones of MI1/2), LeChuck's flyer, the letter and the scrapbook are nice paper supplements and the soundtrack on top is pretty cool, too. From the picture, it's probably safe to assume that it's a very stripped down album with the most important tracks only. That's a pity, but unfortunately I wouldn't have expected more.
At first glance, the only thing I don't like is the poster. LeChuck photoshopped into the sky this way just looks cheap...
The keys I personally do not find so problematic, but of course: For absolute collectors, this leaves a very bitter taste.
After thinking about it for a while, I think I'll pass, because it'll end up just lying around somewhere - and I think $90 is pretty steep. Let's see.
Secretly I rather hope for a vinyl release of the (hopefully not too shortened) soundtrack. For that I would be willing to spend such a price.