Well, it looks like it would be really great. But it's not, at least not in my opinion.
I've been playing the LoL pbe where this has been released recently, and I have to say I strongly dislike it.
Everything is huge, ugly colors, and it is too drastic. I do however enjoy the new items and masteries, but some more than others.
The new jungle is pretty cool, but if one person on your team puts you behind, even jussst a little., then you automatically lose. I think the jungle should just be a bit more weaker, and then it would be fine.