In a nutshell
Both RealAudio and Windows Media (especially WMA9 and WMA10) sound pretty damn good at low bitrates. It's only when you approach the higher bitrates when they lose their edge.
I prefer WMA over RA purely because I hate all the stupid fucking shit that RealPlayer tries to install on your PC. That's also why I use RealPlayer Alternative (google for Real Player Alternative, and download it - it rocks your box mate!). It's basically a hacked apart version of the latest Real Player, so you get a Real Player interface, and it can stream all the RealMedia filetypes, but it has none of the stupid shit - it uses Media Player Classic as the playback engine. It's not 100.0000% perfect, yet, but I've only ever had a problem with it not being able to load a stream ONCE.
That's less times than with a proper copy of the real (Heh) Real Player.
At the end of the day, format wars come down to how easy it is to make the files in the first place. I still think that WMA is better than RealAudio for low-bitrate streaming, but meh I don't have to have the official RealPlayer installed any more so I'm kinda ambivalent.
If we're going to get all argumentative about which filetype > *, then FLAC @ 900kbps plskthx