I have to admit, I'm an old school D&D (and AD&D) player, and stopped playing some time ago. But some friends and I decided not so long ago to start up a new group, and so I launched myself into D&D 3.5.
I wasn't sure whether or not to fork out so much cash for one book, leather-bound or not, but I'm glad I did. Aesthetically-speaking, it's lovely. Slightly padded, very dark blue leather (my friend's is pretty much black) with silver embossed print on the cover, and silver edged pages, it's a really nice book to hold and, if you have the cash to spare, worth the extra just for the luxury. (The only complaint I have is that it's the only book in the set Wizards issued like this for the 30th anniversary last year, but I guess that makes it more special).
As for the content, I'm still getting through it, but I have to say Wizards have really reinervated the whole experience. More experienced players/reviewers might be able to tell you more on the standard players handbook. There is, I must note, a letter from the WotC chief thanking you for buying the special book and he points out that aside from the presentation, they have also amended all the errata from the previous version; it's the most complete, up-to-date version there is.
If you were just wondering about the difference between the presentation of the books and the price, then I fully recommend it. It really is deluxe.