What effect does twitter, facebook have on blogs?

Communications breakdown?

TUCSON -- As I start 2010, the 5th year for this blog, I have to wonder what effect social networking sites such as twitter and facebook, which I use, have on this and other blogs?

I like twitter, and starting in 2009 found it to be much quicker and easier to put out my views to many interested people and link them to relevant sites, especially on my many very busy days.

I also like and cherish my blog, but my blog posting, which for years was at least once a day or more, declined in late 2009, as regular readers may have noticed. I'm not sure right now if this decline will last or not -- likely not with the 2010 Arizona legislative session coming up -- but is it bad to move toward more twitter and less blogging?

Are we tuning in to shorter bits of information with twitter and facebook? If so, is this bad, good or neutral?

What do you think? How are twitter and facebook effecting the blogs?