I've looked into Site.com and it seems like it has a lot of potential, but it's not quite fully baked at this time. I appreciate that Salesforce seems to be working hard on it and look forward to more from them. I'm not trying to be antagonistic here...
Sometimes it is difficult to cut through all of the marketing with Salesforce (and other companies, to be fair) and I've learned that it is never safe to assume that some feature will work and/or be present in anything with Salesforce, no matter how basic, and with proprietary software like Site.com you get what you get.
I'd like to know what are the full lists of deficiencies that others have compiled while using or evaluating Site.com?