Alex has sent me an installer FIR to test - and it works! So, I guess this is the first alpha release for the 500d on the unified tree now
Unified Magic Lantern for Rebel T1i / 500d - Alpha Release



couple things:
- audio_thresholds moved somewhere.. i can't find it, so no working audio meter yet.
- expect bugs: this is the first alpha release where you tell me what's wrong and I fix it

- use at own risk as always.
- docs aren't updated yet for 500D - if anyone is up for the task, it would help everybody a lot!
-
***UPGRADE TO v1.1.1 FIRST***Install Procedure:- Upgrade to v1.1.1 firmware first.
- Download the .zip file and unzip it to your sd card.
- Run the firmware update on your camera
That's it

If all went well, your card is now bootable, and when you turn your camera off/on, it will boot the autoexec.bin that's already on the card, and you're ready to start using magic lantern.
Report any bugs to the official repo:
https://bitbucket.org/hudson/magic-lantern/issuesThe sourcecode to this build can be found in my fork here (until Alex pulls it into the main repository at least):
https://bitbucket.org/coutts/magic-lantern/overviewDownload:http://bit.ly/t1MYYmEnjoy!!!