There isn't anything specific that this could stand for.
NF stands for Now Following on Twitter.
OH stands for Overheard. As in "OH:What makes Twitter so popular?"
PM stands for Personal Message. In Twitter this is a direct message.
It stands for power.
MT stands for "Modified Tweet".
It stands for Follow Saturday.
It stands for Check Your Direct Messages.
'F' could stand for any number of things on Twitter. The widely used 'FF' on Twitter stands for Follow Friday.
MM stands for Music Monday.
T.C.A.P stands for "To Catch A Predator"
DM stands for direct message, so, DMed stands for direct messaged.
yep ! her twitter is http://twitter.com/DaniVJonas :D