I don't think it's reflective of any change in their levels of satisfaction. I think Dreamhost PS represents a new service and that it takes a while for people to realize that they need or like it. I remember when the 3M Corporation sent me a tiny yellow notepad that wasn't glued together the same way that other notepads I'd seen were. It had this semi-sticky stuff that held it together and that stuck to most surfaces pretty nicely after removed from the pad. I had never seen such a thing and couldn't figure out who would need such a thing, but it did seem pretty neat. Over time, more and more people started using it.
I think the same about the new "Easy" one-click installs. Wordpress.com and Blogger obviously provide very similar services, but never when tied to a general-purpose hosting account. Will this see increased usage over time? I'd put my money on it!
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