I got a normal business envelope with a two page letter outlining the terms of my scholarship (scholarship usable at Norwich University *only*, *must* enroll with a Tier 1 major, *must* return the acceptance questionnaire, etc) and a short statement on the third page explaining that they didn't have the money for the big fancy envelope and nice introductory booklet this year. I had to download the booklet from the internet and print it out.
I believe NROTC only begins DoDMERB after the scholarship is awarded, so if "Navy ROTC" pops up on the DoDMERB status page, it's a good sign.