They did announce somit, they said be at earth spacedock for 6pm central for drinks and streamin music or somit.
I must have missed that cause all I saw was the messge that said "The Star Trek Online team would like to extend a special Happy First Contact Day greeting to all of you. May we all live to see April 5, 2063!"
on the front page. It didn't mention anything about an event of any kind.