Welcome back to building, Gary.
I would guess that most builders on this forum use wax paper (I know it's been my choice), but it tends to be a personal preference sort of thing, without a lot of distinct differences either way. I was just reading Don Ross' second book - Flying Models: Tips & Techniques for Beginner & Expert, and he apparently recommends plastic wrap because wax paper can supposedly "get into glue joints and soften them." This was the first I'd ever heard of such a problem.
If you're just getting back into building and are looking for a plethora of great tips, I'd recommend Phugoid's forum topic called
Cessna 180 Group Build,
http://balsamodels.com/phpBB/viewtopic.php?f=2&t=2215&hilit=cessna+180+group+build I believe there might even be an expanded discussion of 'paper or plastic'.
Good luck!