From the games I have played, umm...
VtM: Bloodlines, Fallout 3 & NV, as well as Oblivion are poor substitutes for a stealth game, but they are an enjoyable enough option to scratch my stealth itch. Splinter Cell and Hitman are alright, but the former is too linear and the latter is not sneaky enough for my tastes. Also, both have fairly uninteresting settings, stories, and characters. Crysis stealth gameplay was way too easy. STALKER... I can't really remember if that had stealth, which can't be a good thing. Amnesia was fun, but I enjoy being the predator more than the prey. Deus Ex is fun enough played as a stealth game, but suffers from stupid AI syndrome. Arkham Asylum had fun stealth sections, but they were only sections.
I'm hopeful for the upcoming Thief and Deus Ex titles but nothing out there has mastered the stealth gameplay mechanic quite like the original two thief games did, and I doubt they will either.