I work with very, very large source trees (read several million lines) and svn is a dog. We can't branch because it's too slow, I can't share bits of code with other developers without having them in the 'central' repo, and we can't checkin if there is a major 'official' build being prepared. Therefore, lots of people end up with important changes not checked in until it's done or bust. So much for source control, and 'backups'.
With git, I can switch from a branch to another in less than 5 seconds, on the same tree. I can have several branches with my various 'in progress' project, I can share these with the guy at the next desk without poluting everyone else. I can do merges in many ways, I can /reorganize my branches/ (including reordering/deleting/merging my commits), before committing to the official ones.
And, I can /still/ have a central repository; it's just another repo I call 'origin' and 'pushes' my stuff into so it's backuped.
Sure git doesn't invent anything major, it's just that it's implemented properly and is very fast. I've spent too much lifetime in meetings where the topic was "how can we so this or that with svn/cvs and survive the experience". I actually look forward of merging stuff with git because 1) it's probably going to work automagically 2) I used to postpone for days doing it in svn because of the pain in the ass involved.
And git is non-intrusive, you can use it for other things than source file. I use it in the /etc of my servers, and I even use it on my Eagle CAD files -- no need for an external repo here, but I still have history, tags, diffs and branches. Chrismas.
Oh, and 'linus' is nothing to do with me liking git. I actually think linus is a git anyway. but you have to give him credit on stuff, and git is a small jewel.
