I'm lurking here on the NW forum because I'm doing a long transpac with a friend on NW in April (seats 73 A,B all the way - good seats according to seatguru.com)

Anyway, I flew MCO-CLT 1/16 UGed to F on US. I noticed that US and NW (along with several others) share the same boarding area (Gates 30-59) at MCO. The US check-in agent made notations on my BP, and at Security, the first agent waved me through to the Express line. Result: check-in to US Club lounge took under 10 minutes, and I was very surprised considering the long lines.

Since li'l ol' US has made arrangements with TSA for speedy service at MCO, I wouldn't be surprised if NW has similar arrangements...

Happy travels!