With the arrival of Facebook Places, checking in is going mainstream.  And yet debates have already broken out about how the definition of checking in is changing.  Going beyond a geographic notice, it’s becoming a way to mark a shared experience like watching Mad Men, a rite of passage such as entering your freshman dorm for the first time, or to mark the once-in-a-lifetime achievement of reaching the North Pole.

So what could check-ins do for B2Bs?  Or corporate communications generally?  Are there events that lend themselves well, or even better to checking-in than the way they’re communicated now?

Let’s brainstorm a list and send it to LinkedIn.  To start things off, here are five check-ins that companies could find useful.  And for fun’s sake, five more that no company would want to make.  Add your suggestions in the comments, anonymously if you prefer, or with your name for public credit.

1. Quiet period
2. Six Sigma status
3. Product phases, like Research, Development, Prototyping, Piloting, Launch
4. Company phases: Start-up, small, mid-sized, large, multi-national, global, Fortune 1,000
5. Geographic expansion: Checking in to New York, Rhode Island, the EU

And status updates that no companies would want to check into:

1. Audit
2. Lawsuit
3. Investigation
4. “The Red”
5. Strike