Terms:
Pod - I agree or I concur
Used in a sentence: Pod! You were so right to ditch that loser boyfriend
Snarky - usually means someone in a sort of foul mood.
Used in a sentence: Because it was cold and rainy today, I ended up being in a really snarky mood.
Squick, Squicky - a combination of the works squeamish and ick(y). Used to described something that is probably disgusting and might make you squirm
Used in a sentence: Ewww! I don't want to touch that pumpkin goop. Squicky!
Abbreviations (these can also be found at the Etiquette Hell website under the link abbreviations):
AFAIK - As far as I know
BF - Boyfriend
BIL - Brother-in-law
BM - Bridesmaid or Best Man
BTB - Bride to be
BWW - Big White Wedding
DD - Dear Daughter
DH - Dear Husband
DIL - Daughter-in-law
DS - Dear Son
Ehell - Etiquette Hell
ETA - Edited to add
FBIL - Future brother-in-law
FH - Future husband
FIL - Father-in-law
FOB - Father of bride
FOG - Father of groom
FSIL - Future sister-in-law
FMIL - Future mother-in-law
FTB - Father-to-be
FW - Future wife
FWIW - For what it's worth
GF - Girlfriend
GMIL - Grandmother-in-law
HC - Happy couple
HTH - Hope this helps
IANAL - I am not a lawyer
IIRC - If I remember correctly
IL - In-laws
IMO/IMHO - In my opinion/In my humble opinion
JOP - Justice of the Peace
LDH - Late Dear Husband
MIL - Mother-in-law
MOB - Mother of the bride
MOH - Maid of honor
MOG - Mother of groom
MOTB - Mother of the bride
MTB - Mother-to-be
OP - Original poster
OTOH - On the other hand
PA - Passive-aggressive
PITA - Pain in the bottom
RSVP - Répondez s'il vous plait (French for "Respond, if you please")
SAHM - Stay at home mother
SIL - Sister-in-law
SO - Significant Other
S/O - Spin off, as in spin off thread from another thread
TMI - Too much information
YMMV - Your mileage may vary
PM me any new ones you can think of so I can edit the post.