Negative Messages... OK

[KieranDotW]

Just gonna leave this here. It's still like this, I swear I didn't photoshop anything.

 

[Simplicated]

I also got this yesterday, Messages on OS X is really a buggy piece of software.

 

[vmachiel]

Got that once two before 10.8.2 and iOS6 with their phone number/Apple id merger. Check settings, are both your phone number and your apple id present on all devices?