Hazaro said:
The two crowds watch for different reasons.
I've met a few people who only watch HD and Husky but haven't seen a single GSL match.
It's not Husky or HD's fault though; both try to be members of the community yet have been shunned by many folks. HD is not a bad player - he's masters and probably better than most of Teh Hardcore players who hate him; not a great caster, but he's certainly more knowledgeable than someone like DjWheat. Husky admits he sucks but clearly loves the game and is a good guy (see: TotalBiscuit's story).
I see both as entry points for fans. They're a lot of fun and introduce you to the basics, then you might move on to GSL/MLG/etc; that makes them quite important, they're essentially gate keepers. I've got two brothers who love SC2. One only watches Husky/HD to this day, the other has moved on to Tastosis/others. The one more into Husky/HD will watch a big SC2 tournament when I am, but when left to his own devices he'll stick to what he knows.