I haven't been watching closely, but dev-lang/R-2.3.0 has moved into alpha test
status with the release scheduled for April 24, 2006. I'm testing it on Athlon
T-bird, Athlon XP and Pentium III. I may get a chance to run it on a P4 as
well, but I'm not sure when.
Here's the "changelog" for those who care, as of this posting:
https://svn.r-project.org/R/trunk/NEWS
I didn't see anything that looked like it changed in the install, so the ebuild
should be a simple version bump.
Released Monday, April 24, 2006. It should have propagated to all of the
mirrors by now, but if it hasn't, the mother lode is http://cran.r-project.org
in Austria.