Count me as happy about the split. There was a period of several weeks very recently, on Debian unstable, when totem wouldn't play anything, but smplayer continued working (mostly) fine. When two interchangeable products are equally buggy, the split is helpful when the bugs don't overlap much.
This is similar to how you can use ffmpeg from DirectShow or QuickTime. It's pretty nice and is usually one of the first items I install on a new Linux system.