I've spoken briefly with some of the folks on the Tcl Core team, who suggested that this version of Tcl be called "ParTcl"
Right now, I've got a big chunk of the interpreter working. Next two big steps are overhauling [expr], and swapping out the generic (and Perl) PMCs for dynamically loaded Tcl PMCs. Now that Parrot 0.1.1 is released, I should be able to switch over to the dynamic PMCs without a problem.
Once those are done, I can add in/flesh out all the tcl builtins that rely on lists and arrays. (Or, if you speak perl, arrays and hashes. Mostly).
Volunteers welcome. ^_^