I don't know how to get the debug logs.
Here is the timing for my two cards mmcblk0 being the Transcend 150x 2gig (internal) and mmcblk1 being a not even specced (none included in blister pack) Kingston 2gig. I tested before installing the sdhc kernel and the mmcblk0 was 32 secs and the kingston 34 secs, didn't screen cap it :/

the results below are unexpected, I expected the transcend to be in line with the other results here, the kingston I expected nothing from and I got a roughly 1/3 gain.
Cliff

Nokia-N800-51:~# time dd if=/dev/mmcblk0 of=/dev/null bs=8192 count=30000
30000+0 records in
30000+0 records out
real 0m 20.91s
user 0m 0.03s
sys 0m 3.69s
Nokia-N800-51:~# time dd if=/dev/mmcblk0 of=/dev/null bs=8192 count=30000
30000+0 records in
30000+0 records out
real 0m 20.93s
user 0m 0.04s
sys 0m 3.78s
Nokia-N800-51:~# time dd if=/dev/mmcblk1 of=/dev/null bs=8192 count=30000
30000+0 records in
30000+0 records out
real 0m 21.59s
user 0m 0.07s
sys 0m 3.88s