Respawn Entertainment has been granted a trademark by the United States Patent and Trademark Office for the name Titan to be used for video and computer game programs. I looked in the EU trademark database and it appears a trademark hasn't been filed or granted yet in Europe.
This and the tweet by Vince Zampella that he wouldn't show up at E3 this year empty handed probably means that an announcement isn't far off. I'm wondering at whose stage the game will be announced.
And It appears the Blizzard game codenamed Titan can't be named Titan for real now.