In case you missed it, Mayor Leffingwell has formed a group, the Central Corridor Advisory Group, to hash out the alignment of Austin's first urban rail line. AURA has a representative on the CCAG, Julie Montgomery.
On a related note, here is a very neat map of a possible Guadalupe-North Lamar alignment, prepared by Scott Morris of Central Austin Community Development Corporation, which I'm reprinting by permission:
I wish I had the graphic skills to do this kind of thing, but I don't. I'm glad Scott does.
If I have a criticism of this proposal, it's that it might have too many stations. The reason he shows so many stations, of course, is that this route is so destination-dense. You can justify putting a station just about anywhere along this line.
Update: Scott sent me a revised map, which corrected a typo and made some minor changes. I've updated the original map with the revised map. See also Scott's comments below for additional explanation, and his web page, which has a lot of great analysis supporting his specific proposal, and the Guadalupe/North Lamar alignment in general.