With the opening of Costa Mesa 55 Tavern & Bowl in what I am guessing is the space left behind by Virgin Megastore (or was it the Nike Town?) The Triangle looks like it has most of its vacant space occupied.
The revitalized complex at the end of the 55 freeway has been slowly transforming itself from a dying retail center to one focused on restaurants and entertainment. El Cozaron, Saddle Ranch, H2O Sushi, Olive Branch and Black Knight opened over the past year.
Costa Mesa 55 Tavern & Bowl is the fourth of its kind. There are three other Tavern & Bowls in San Diego county. The online menu reveals typical bowling alley fare of burgers, pizza, and hot wings. A burger named "The Dude" looks like it's offered at the other branches, but not at this one quite yet. I expect it will soon, because what's a bowling alley without at least one Lebowski reference.