I was early adopter with Vizio 552. This was my first HDTV purchase and I "didn't know what I didn't know". I wish I had of bought the tried and true 551 at a reduced year-end price.
Unfortunately, I believed promises of features to be enabled after shipment via firmware updates, etc. I'm still waiting for usb ports to be enabled, firmware update to fix a firmware update that broke TV setting and now it's almost a new model year. I just don't believe anymore, unless I see it myself first.
I like the picture on my set, but important features were missing that I didn't realize the importance of at the time, due to my inexperience. Also, as an early adopter, I had only the website for descriptions of how menus and services would look like, and how they would function. As it turned out there was precious little information there, and the manual was wrong.
Edit: By the way, advertising 3 USB ports when in fact none work is plain false advertising imho and should not be allowed.