Okay, I've had SubText up and running for a week and some now, so naturally it is time to tinker. In poking around, I'm not as happy with SubText's integration model as I was with DasBlog's. DasBlog exposed a number of "macros" that you could use to insert certain internal values into your own stuff. I kind of liked their model because once you registered your own code, you could reference your macros from DasBlog stuff as well (bear in mind that I didn't actually implement DasBlog, so my impression could be off).
That said, as long as you don't need to...