I have experienced tremendous results this year by changing how I train biceps. I train them as frequently as possible. That usually means once every 3-4 days. I can get away with this frequency because I only use 1-2 all-out balls-to-the-wall sets (obviously, not including warm-ups).
I religiously use a 3-4 second negative on every rep. The eccentric phase is really important, probably even more important on smaller muscle groups than the big ones. I also use rest-pauses in all of the working sets. You can move really heavy weight and still hit a solid rep range (I like the 15-20 range).
Lastly, I make sure to either beat my weight or rep count from the previous workout. This is very important. Because, all things held equal (& discounting CNS adaptation, etc.), if you're getting stronger, you're getting bigger. You're forcing your muscles to adapt to the greater load. Do this consistently year after year, and I guarantee you'll be carrying a larger musculature.
My favorite biceps exercises are dumbell preacher curls, incline db curls, spyders, and to some extent standing curls (bb & db). I rotate all of these exercises to prevent monotonous training and make it humanly possible to beat the numbers on a consistent basis, LOL.
On Saturday, I preacher curled the 65 for 14 (8-4-2) with a consistent 3-4 sec. negative. That's pretty friggin' heavy. All I needed was one set and my bi's were destroyed. They're still a bit sore today.