I think the Saw franchise is pretty unique as it's a series of "extreme thrillers" who seemingly flirt with the Italian giallo genre as well as the US survival horror genre.
I really think we need (and will get) a part 8 though,because 7 was disappointing in imo and really was no fitting ending.
There's also a lot left unexplained.
If you're into Saw,check out:
House of Jigsaw - Powered by vBulletin