In reply to:
Is this really common? Do I need to look around again?
Frankly, all the complaints about downtime are a complete mystery to me. I've experienced very little downtime since transferring various domains to DreamHost just over a year ago. I've had the occasional email outage of note, and once or twice there has been some MySQL problems, but any outages have been very minor when compared with other hosts I have used.
Some servers seem to have more problems than others, so my experiences may be atypical; however, I've had no experiences that would prevent me from giving DreamHost my highest recommendation.