I actually owe marcus an apology.
You were correct in that Moose startup time has not gotten significantly faster since 0.01. After our exchange Sartak decided to actually take a look and see. So he wrote this script, which produced this data, which jhannah then promptly turned into this graph (reproduced below).
It seems that since the 0.15 release we have mostly stayed within the 0.2 to 0.3 second range. It is interesting to look at the Changelogs for both Moose and Class::MOP you can actually see the feature additions or refactorings that correspond with the peaks and valleys.
Some of the most recent speedup is the direct result of Goro (gfx) Fuji's work on Class::MOP and Moose as sponsored by the Japan Perl Association. Much thanks to all involved in that.