Let me just touch upon the features of Chrome that make it suitable for such complex applications.
Any good Operating System will try to avoid memory fragmentation and reclaim unused memory effectively. Chrome does this by creating a different process for each tab and using a thorough garbage collection mechanism. Chrome comic book explains this clearly if you are interested. Yes, it will take up more operating memory than Firefox due to multiple processes but then Chrome is not just a browser. It's a platform for complex applications that will require lot of memory themselves.
So, the next time you see somebody ignoring Chrome as just another browser, tell them it's not. Chrome is getting ready for the future of Internet. It's just that the Web is not ready for Chrome yet.