Banshee evolved greately in the last releases: start time, more plugins are around, it works in the most use cases of RythmBox.
The last releases are also capable to see videos, and have a pretty decent organizer. So users may enjoy to have a media music manager (no only radio and mp3 one).
I still think that Banshee cannot replace totem as default player as it does not have support for subtitles (or an obvious way to pick them).
For Mono haters: Ubuntu ships with FSpot, which happens to be a good media library for photos, having a Mono music organizer, may sounds good also. In the meantime, if the change will happen, for 9,10, Mono will probably be at the 2.2 version, so it may make Banshee a bit faster (this is the main theme of Mono 2.2 version)
- the autor states that will make a win of 6 MB on CD also. Which is great from that switch.