I know some people like it, but I find the top menu bar on a mac extremely non ergonomic. The argument goes that it's an easy spot to hit: Just move your mouse to the top. But they forget that in order to use the menu bar you have to activate the app! In other OS's, if you want to pick an item from an inactive app, just click - it will activate the app, and pick the item from the menu bar at the same time. Not so wit…
Ok so you get more screen space I guess, but IMO it's not worth the trade off.