We’ve known for a couple of weeks now that Danny Meyer’s wildly popular N.Y.-based Shake Shack was coming to the Westfield Century City Shopping Center.  But apparently, the burger stand will be bigger than originally thought.  The first plywood went up over the space on the second deck that housed Solstice Sunglasses.  But recently, the plywood has crept closer to Obica, swallowing up the mall’s outlet of smoothie chain Jamba Juice in the process.  No word on Shake Shack’s opening date, but I’ll keep watching.