Ok, here are my numbers using 5000 lines of uuencoded kernel.
vgafb wscons code:
0.0u 9.2s 0:09.29 99.3% 0+0k 0+1io 0pf+0w

orig wscons code:
0.0u 0.1s 0:00.19 84.2% 0+0k 0+1io 0pf+0w

xterm:
0.0u 0.0s 0:00.36 0.0% 0+0k 0+1io 0pf+0w

This is on a -current Duron 950 system with a TNT2 Ultra and X 4.0.2.

So, it is quite a bit slower.. but still very nice to have. :)  I wonder
how hard it would be to allow switching back and forth with text mode?

-Andrew