So, if I understand this correctly, now that I've done an xBackup backup and am downloading 2.0.4, my next steps should be:
1) Connect to iTunes and sync (or should it be 'back up'?).
2) Do an update to 5.1.1 (or do I need to restore first?).
3) After 5.1.1 is installed, do I have to do anything (like sync) before running absinthe?
4) Run absinthe.
5) Once absinthe has finished jailbreaking 5.1.1, go into Cydia and re-install xBackup.
6) Run restore on xBackup.
Any advice on the first three steps - on which I'm still a bit confused - will be appreciated, along with pointing out anything I'd be doing wrong in the above procedure.