Try to think of shmup as a fun/funny term. Say it with a bit of an accent, or mess up the word itself and it beco on a bit of a gag.
Shmip, shrimp, shump, skibidishmipbashmuh.
PM = Private Message
DM = Direct Message
(They're both the same thing)
YMMV = Your mileage may vary
IMHO = In my honest opinion
(just for your reference, in case you're listing things you don't know)
I too hate that graded is the default. It makes zero sense from a general consumer standpoint. TBH I could see that actually being a driving factor in moving a lot of people away from the service - nobody wants a whole-ass extra click EVERY time they search a game.