First off, yes, they will take your phone and give you a claim ticket to retrieve it after the taping.
With a Priority ticket, as long as you're there by 1pm, you'll be guaranteed entry. I'd say get there 1/2 hour to an hour earlier just for good line positioning (even though it makes not difference on where you may end up sitting in the studio). When you go through the gate, you'll get some paperwork to fill out. Don't know how it was in the Barker days, but it's simple stuff. Any game show appearances, initial on one of the middle pages, and then signature, date, and last four SSN digits. During this time they'll run a best of compilation video on the monitors and get your name tag. You'll hand your paperwork and ID to one of three OCA people sitting behind some showcase podiums. They'll double check that you did everything correctly and then take your picture. After that, there is indeed a green screen to take pictures in front of both by yourself and with a group if you're with one. You'll then wait on benches to be interviewed by Stan, something I'm assuming probably hasn't changed much. While you're waiting, if there's time, people with the photography company that took that green screen photo will come up to you, show you your photo(s) and ask if you want to purchase it. If you buy one right there, they'll print it out for you and you can collect it before you leave the lot. You can also wait and buy it online later, though it's $10 cheaper if you buy it there (in addition to a physical copy, they'll post the photo unwatermarked to their FB page and you can download it there).
Once you've done the interview, you'll head around to another set of benches where they'll take your phone, issue you a claim ticket, and walk you through a metal scanner. They have TVs there and once around 150 people or so have begun to file in to the area, they'll play a recent episode of the show. Having been a few weeks ago, it's more than likely going to be a show from last season. While in that area there is also food available for purchase, don't know if that was there in Barker days either. Once even more people have filed in, they'll play a warmup video featuring George and Rachel. It's a fine enough video, but it's from Season 43, so the set is noticeably different and it's missing more memorable moments from the last few seasons. They should really update it.
