I havent looked in detail at the barebones that are being offered recently but this is what i know from my experience...
At first they always seem like a really good deal, but usually when you look more into them, they arent as nice. They always seem to give bad motherboards that are not going to be good if you plan on expanding or upgrading in the future. Also, they always give you generic RAM, which in my opinion is one place to never cut down on, with not great specs. The case and psu usually does the trick especially if you go with one of the new intel processors (they dont require too much energy). The video cards offered tend to advertise just if its 256mb's or 128mb's, which can be misleading since thats not the only thing that matters. All in all, they are a good deal for lower end computers with no potential for the future. I wouldn't waste my money.