Q: Old apple monitor seems different than one in store

I have, according to "about this mac", a 24-inch, late 2008 (1920 x 1200) display. I was considering getting a thunderbolt display and daisy chaining (with a hard drive in the middle). The thing is, I was looking at the display in the apple store, and it seems smaller than mine. It looks wider (actually, it just looks like the heigh has decreased, therefor making it seem wider). Is this true? Have the displays changed since I bought mine?