This is a really great idea. I just started using Sublime Text 2, and the Goto Anything feature is brilliant.
However, if there was a way to goto symbols in a cross-file way, that'd be awesome. I presume this would mean the editor would have to keep an in-memory index of all symbols in your project so it's fast enough. (I don't mean an index file like ctags, because Sublime already knows what symbols are based on the language definition.)
For instance, you could type something like Ctrl+P then "@@my_func" to start searching for the symbol my_func in any of your files.
Would it be possible to do this via a plugin?
At present, do most people do this using Find in Files? (Not as slick, because it'll match more than just symbol definitions, but does the job.)