To give you some idea on how long Apple actually approves apps, I’ve posted here the schedule for 2 versions of my Message Scrambler app. One version went to “Waiting for Upload” state on March 1st, and went to “Ready for Sale” state on March 5th.

The next version, I submitted on March 16th, and went on “Ready for Sale” state on March 22.

So you can say, it takes around 5 or 6 days, assuming there are no issues on your apps. I heard cases where Apple would reject the app because of some issues (crashing issues, etc). In these cases it would take longer.