A more simple way without going to the Monitor Screen is to tap on the blue "Uploads" tab in your "Library". Tap on it until the small arrow is facing Down & then all of your Uploads will show all files being transfered. For instance, below the Uploads tab are these "0/0"s. When someone is downloading from you, it will show "0/1" or completed transfers will show "1/1". Thats on the 3.0.1 & the new 3.1 Beta. Don't remember what shows up on earlier versions.
Have Fun!
Jimbo.