I'd say another big game changer is going to be APIs becoming ubiquitous. A lot of sites are already doing this, but in the next few years, expect even more open APIs from even more sites. Screen scraping should become largely a thing of the past. I expect the Internet to take on a Unix philosophy with web apps becoming very well suited at individual tasks instead of kitchen-sink type applications. Information will be passed in XML (plain text or gzipped), apps will be strung together fairly easily if we keep pushing for RESTful APIs, and the winners will be the people that build on other sites in useful and ingenious ways.<p>You can already see this with Twitter. A social networking site that is basically just the status field from Facebook being utilized for all sorts of other tasks because they have an open API. Expect to see more sites take individual features from other sites (or create completely new features) and build really great services with just <i>that</i> feature.<p>For this to happen, a ubiquitous login is going to have to really take hold, but I already see that happening with Facebook Connect. It's proprietary, but they've already reached critical mass and it doesn't break the username/password paradigm that people are used to. OpenID, while great in concept, is going to lose because people aren't used to having a URL represent them.