Re: install bet now, upgrade later
If you install 13.04 now, and keep up with the normal system updates, you will have the release version on release day. Even the people who have been using 13.04 since development started in November will have the release version if they keep their system up-to-date.
It's definitely safer to install 13.04 now and do a couple of package updates on release day, than it is to start from 12.10 and upgrade the whole way. It's also much easier on bandwidth and willl be much quicker. There are probably only a couple of bugs in 13.04 today that won't be present in the release version in a couple of days time, and you'd only be updating maybe ten or twenty packages instead of 450 packages that you'd be upgrading when going from 12.10 to 13.04.
My recommendation: Install 13.04 Daily, and just run normal system updates every day (as you would, anyway).
I try to treat the cause, not the symptom. I avoid the terminal in instructions, unless it's easier or necessary. My instructions will work within the Ubuntu system, instead of breaking or subverting it. Those are the three guarantees to the helpee.