I am a huge Tarantino fan and I also love Reservoir Dogs, Pulp Fiction and Jackie Brown but I didn't like Kill Bill. It is nothing like his other work, so first of all don't expect anything in the vein of those other ones.
I have only seen Kill Bill Vol 1, the first half is ok, still doesn't hold a candle to his other films but has some typical quirky Tarantino magic and some good scenes but then it basically turns into an overblown parody of Hong Kong action, Japanese anime and as Wicked Child said a touch of spaghetti westerns as well. Personally I've never been into Hong Kong action films or Japanese anime so I didn't like it.
The end has a good twist though and actually did leave me wanting to see Volume 2 just to see what happened next and I think Volume 2 will be better because the Japanese part of the story is over so I'm guessing there won't be any martial arts stuff.
But as I said, still nowhere near the league of his first 3 films.