I've found myspace quite useful, in the sense that people like like to see me play but I don't see often are more likely to stumble across stuff on there than visit my website lots. And whether I like them or not a lot of the kids in our local clubs go on there, so it gets word out and it's got people coming to (particularly) benefit gigs I've played at which is always good.
It has it's uses, I just try to remember when I put something interesting on my site to quickly log in to myspace and paste it there. Don't take much time.
Yeah, there's lots of people who plaster flyers for their stuff on my page, but it don't really bother me, particularly as I don't really wanna make this a job, just wanna make a few tunes and play a few gigs that give a few folk some fun...