That's debatable...
http://en.wikipedia.org/wiki/Singular_they#Grammatical_analysis
The Wikipedia article has a lot of good info on it. I also just read what Grammar Girl has to say on it. I think it's debatable to use "they" in the signular form in common English, but it's still against "the rules" in formal documents. Either way, it's hardly worth spending much time on.
Thanks!
-EWG
When someone disconnects in a live game it says:
"SOMEONE has disconnected. They have 2 minutes to reconnect..."
Correct English would read:
"SOMEONE has disconnected. He or she has 2 minutes to reconnect..."
Note the plural they vs the singular pronouns of "he or she".
Respectfully,
EWG