ICYMI
In case you missed it
Example
ICYMI - the last episode of Seinfeld just aired

Related Slang
ICYWTBE | In case you went to bed early |
JIC | Just in case |
ICE | In case of emergency |
ICYC | In case you're curious |
bup | Backup Plan |
FWIW | For what it's worth |
ICYMI is an acronym that means in case you missed it. It is often used on Twitter, blogs, or social networking sites.
The acronym is usually associated with a news story that was buried by another event or that took place late at night when people were sleeping. It commonly prefaces a link that redirects to a news story, or possibly to another "tweet" or blog post.