Iit's always a bit strange to see how many people hack features in GM scripts. We've observed this at work, too: Mihai hacks gmail features rather than implementing them directly for two major reasons:
- It's much easier to write a bit of Javascript than it is to check out, learn the code base, and especially get a whole {gmail,lj,etc.} install going. Even back when I was comfortable with the first two of those steps for LiveJournal development, the last one was enough of a hurdle to discourage me from writing features.
- Even after you've implemented a feature, many of them are policy decisions -- like the userscript to make all profile links on LJ be "full" links -- and they're unlikely to be incorporated upstream anyway.