Ok I attached a new patch that solves the things you mentioned. It can debug Python inferiors with versions 2.6+. Execution control commands (py-{run, cont, finish, step, next}) and py-exec need gdb 7.2+, py-break works with 7.1+.

It now also "supports exceptions", which means that if there is a pending exception when control is transferred to the debugger, the exception is printed (safely).
Also stepping and stepping over should be a lot faster as it now uses hardware watchpoints that watch the instruction pointer (f->f_lasti).