I love my MBA 13". I was looking at getting a TB display for a bit more screen real estate but at $999...wow...it is almost the cost of an entry level 21" iMac ($999 versus $1199). The iMac has quad core, AMD graphics, HD FaceTime camera and more. Now I'm thinking - maybe I should figure out how to have both computers and share my data between the two. I cart the MBA between work and home everyday so need the portability but with the price delta so small between the two I'm finding it hard to justify the TB display. Is there much of a difference between the 27" TB screen and the 21" iMac? I suppose a trip to the apple store is in order to check them out. Any thoughts or anyone in a similar situation?