Thanks for your comments.

It seems that people mean different thing by "project." What I mean is a sidebar or preferably a drawer wherein I can organize files in manner independent from the file system (like in Textmate 1.x, Xcode, and many other editors and IDEs). This is necessary to work efficiently for many people. I write many projects which pull resources from many places in the file system where they are organized by differenter criteria, i.e., by language and functionality. Using the Finder to manage a folder with aliases or symlinks is not a good option because I can't order the items the way I want to, but rather be forced to accept the ordering that the new file browser sidebar says I have to (e.g. by name or modification date, I suppose).

I will admit that I don't undersand what is going on with .tm_properties (I scanned the link, and am partially following the discussion on the mailing list) but so far I don't see any indication that .tm_properties solves my problem. I also understand that "project" can mean a means of directing TM to do certain operations on certain files depending on context, etc. That is all fine, but again, doesn't fix the relatively simple problem of providing a sensible organizing tool.

I also note that the developer says, "We don’t intend to restore tmproj files — there is a file browser... [explanation about how great the New World is].... "if you still feel hindered after some weeks, let us know about it." So maybe there is some hope.