That's an easy question for me. I love music, I like 9th wonder, scram jones, needlz, etc etc. But as far as the best goes: It's Timbaland and The Heatmakerz.
NOTE: Dre. is no where near my top 10 list. Why? I like the kid; I love the kid. He has good beats, but his shit is way too scientific. All of his beats follow the same pattern, theres nothing organic about his sound i mean he just picks a drum loop and loops it as well as a 3-4hit string loop. Theres ultimately no progression throughout the tracks, and bass and drums especially virtually drive the music. I love his shit, it's just that when you're going to release a track for the entire world to hear, I don't understand how you can just play one fat loop and not progress the track anymore. It's a shame.
But Timbaland, pure fire. Heatmakerz, pure insanity. They can manipulate virtually any vocal sample into sounding how the want it to. Shit is crazy, I mean most of their melodies are driven by sample vocals, then accented by their insanely progressive drums. Even they have one big loop going, but inside that big loop theres about 4 main individual drum loops that alternate, and a few bridges as well. And the ever-so-frequent let the track trip with theyre crazy repeat drum styles. love it love it shits so hot. Timbaland has the "I can actually make my own beats from scratch" department down, and on lock. And The Heatmakerz have the "We sample and we show you how to do it right" department down. I mean for me, it's all I need in music it's the two opposite ends in the industry almost.