Another thing that would help bitcoin adoption:

python, perl, php libraries and common code for interfacing with bitcoin.

For example, Perl or Python code that verifies that "17NdbrSGoUotzeGCcMMCqnFkEvLymoou9j" is a valid bitcoin address, and "098123409813lkjasdflkjasdflk" is not, would be useful to anyone wishing to implement a bitcoin web interface.