I've heard that since THE LION KING moved to the Minskoff, it hasn't been as powerful as it was before.
I have seen both (I saw THE LION KING back at the New Amsterdam), and I would recommend MARY POPPINS over LION KING in a heartbeat. The opening number of LION KING is quite amazing, but from that point on, it's a snooze fest. MARY POPPINS is very lively and, as others have said, has been around for a much shorter time, and therefore is completely fresh in every respect.
"Winning a Tony this year is like winning Best Attendance in third grade: no one will care but the winner and their mom."
-Kad
"I have also met him in person, and I find him to be quite funny actually. Arrogant and often misinformed, but still funny."
-bjh2114 (on Michael Riedel)