As a few people said already, this does not solve the accessibility problem that comes with text-indent. Worse, it may send the wrong message: “this is new and cool, use this from now!”.
As a leader in the industry, I think you should warn people that even if this is “better” in term of performance, it is still a bad solution.
Imo, Image Replacement techniques should be evaluated against the problems they solve/address. Fwiw, I wrote something about these challenges a few years back:
http://tjkdesign.com/articles/tip.asp </shameless plug>
cool
