I have been playing warwick since season 3, I have about 400 ranked games with this champion and my skillscore is about 4,2k and still growing. I believe this build is rather a powerful one.
I also got with this (with minor and on going tweaks) from bronze 1 to Gold 4 in solo ranked, where i am now and as you can see on picture below.. it is still valid and helps me get even further.
Obviously i am going to improve this guide in time, i just felt that it is about the time i shared my experience with this champion.
This build is good for both top and jungle. You dont need so much of magic resistance from talents, because your items will provide you with enough of that. The most improtant talent of all is Second wind which has an amazing synergy with warwick's passive, his Q and ulti. This is even more boosted by Spirit visage item. Basically, when you get low on hp, you can easily heal yourself prety fast up.... i have seen it many times in fights.. that i survived and killed most of the opponents thanks to this synergy.
I also include someAD dmg runes just because it helps you a lot in early top / jungle farming. You dont need talents for cooldown reduction, because my item build is already quite focused on that