The “King of Pop” is scheduled to make a personal appearance Thursday to announce plans for what is rumored to be the “greatest comeback in history,” say inside sources. Jackson flew into London by private jet Tuesday ahead of a “special announcement.”

He is expected to announce a 30-date marathon at the 20,000-seat O2 arena in London, England, which would set a new record for the longest run at the venue. The current record, held by Prince, came from a 21-date run back in 2007.

Ticket prices for the Michael Jackson’s shows are also expected to top the hugley pricey $700 ticket set by Barbara Streisand for her comeback tour. It has been more than a decade since the pop star launched any substantial tour. The announcement is at 4 p.m. London time on March 5th, 2009.

In April, Jackson will auction more than 2,000 personal items from Neverland, including platinum and gold records, a customized Harley Davidson and a Rolls Royce limousine.