We've been on Dreamhost since 2001 and besides a few hiccups have been excellent. Their control panel is top notch. Our forum is pretty busy with an enormous MySQL DB and I host a few other sites as well on our account, and we were on a standard shared account until this summer when we moved to a VPS. If you start suffering performance issues and are running multiple sites I do believe it makes more sense to have a couple shared account before moving to VPS, because our hosting bill has gone from ~$10/month to more then $60/month. VPS memory is priced per month BUT is prorated so if you move things up and down during the month you only pay for what you use, not for the most memory used for the month.
Dreamhosts add-ons are super cheap too, SSL cert for $15 is a steal!
