Open System Preferences -> Time Machine. At the bottom of the window you should see a line saying something like "Show Time Machine in menu bar". Tick it. Now you have the TM icon in your menu bar. Whenever a backup is running, click on it. You will see how much data is already backed up and how much data the whole backup is.
If the backup is not running, it shows the time of the last successful backup.
I don't know, I use bootable clones myself and it shows me the progress of the backup and updating of files.
However I can point you to this guy who is the local TM guru
If you want to learn more about all sorts of backups to diversify your restore options (TM can fail to restore properly), including bootable clones etc. then read my UT here on the subject.
I personally don't use TimeMachine, preferring the more advanced bootable clone options.