I was in a shop just last night asking the people there this same question. They told me it would cool the smoke down... then I asked how they were compared to bongs and they said it was just a difference in portability.

I was looking at the small bubblers... which are pretty sick in my opinion. I'm sure bubblers cool the smoke a little, but I can't see them being able to compete with a bong full of water and ice. But if you're comparing just a straight pipe with a bubbler then I'd assume the bubbler is better.

On a side note, does anyone know why a tiny bubbler is almost $20 more than a medium sized heavy glass bong???