But recently I've started to see more and more adverts substituting the good old vendor URL for a Facebook version, e.g., moving from www.mycompany.com to www.Facebook.com/mycompany. Now at first this might seem fairly innocuous, but when you dig deeper it's anything but! As I think Tim Berners-Lee has stated elsewhere, and I'm sure Google has too, the data that Facebook is maintaining isn't open for a start, making it harder to search outside of their sub-web. And of course this is like a data cloud in some ways: you're offshoring bits of your data to someone else, so you'd better trust them!
I don't want to pick on any single vendor, so let's stop naming at this point. Even if you can look beyond the lack of openness and the fact that you're basically putting a single vendor in charge of this intra-web, what about all of the nice things that we take for granted from http and REST? Things such as cacheing, intelligent redirects and HATEOAS. Can we be sure that these are implemented and managed correctly on behalf of everyone?
And what's to say that at some point this vendor may decide that Internet protocols are just not good enough or that browsers aren't the right view on to the data? Before you know it we would have a multiverse of Webs, each with their own protocols and UIs. Interactions between them would be difficult if not impossible.
Now of course this is a worst case scenario and I have no idea if any vendors today have plans like this. I'd be surprised if they hadn't been discussed though! So what does this mean for this apparent new attitude to hosting "off the web" and on the "social web"? Well for a start I think that people need to remember that despite how big any one social network may be, there are orders of magnitude more people being "anti-social" and running on the web.
I'm sure that each company that makes the move into social does so on the back of sound marketing research. Unfortunately the people making these decisions aren't necessarily the ones who understand what makes the web work, yet they are precisely the people who need it to work! I really hope that this isn't a slippery slope towards that scenario I outlined. Everyone on the web, both social and anti-social, would lose out in the end! Someone once said that "just because you can do something doesn't mean you should do something."