When browsing from my HTC Droid Incredible, running Android 2.2 w/ Sense, code blocks are not fixed-width.
Minor issue, no doubt.
The pre style defines a LOT of standard fonts that work across Windows, Linux, and Mac.
font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, serif;
none of those fonts work on the Android browser? I dare say that is not a bug in us.
edit: also possibly related to
Not enforcing fixed width font family