Based on my 3GS running iOS 5.1, all of your screenshots are way too zoomed in (update: would be more accurate to say the text is much larger than on my iPhone). And no weird gray background issues like you have for 'bare' mode. FYI, portrait mode seems barely useable due to the small text, while landscape mode is much more readable (normal or bare). As a side note, I had to use http://www.perlmonks.org/bare -- without the 'www' I was served the normal version.
Update: PM looks fine on an iPad2, especially in landscape mode.
