But most fans are more predictable. How do we know? Because nearly three million have now logged questions to the former Beatle on the Internet in what could be the biggest-ever question-and-answer session.
Indeed, it could be regarded as the first global interview. It is certainly the most interactive of publicity exercises, all in aid of Sir Paul's new album, Flaming Pie, which he has recorded with his wife, Linda, and fellow ex-Beatle Ringo Starr.
By last week more than 2.5 million people had sent a query to http://www.vh1.com - and the figure was rising so swiftly that it could top 10 million by the time Sir Paul sits down at a computer screen next Saturday.
At the Bishopsgate Memorial Hall in the City of London he will go online to answer as many as he can in 90 minutes. The whole event will be screened live on VH1 satellite television in Britain, the US and Germany.
Geoff Baker, his spokesman, said most of the questions concerned his music, his source of inspiration and the recent Beatles Anthology of previously unpublished recordings. "The three subjects which keep coming up again and again are variants on: could Paul explain the origin of Flaming Pie, the title of the new album; will he be recording any other new songs with George and Ringo; and when will he be going on tour again?"
The answer to the first is curious and goes back to 1961. Asked about the Beatles' name, John Lennon wrote a piece for a pop newspaper headed Being a Short Diversion on the Dubious Origins of The Beatles. He wrote: "How did the name arrive? It came in a vision. A man appeared on a flaming pie and said unto them [John, George and Paul] `From this day on, you are Beatles with an A'." It was a joke.
In the past few days, some cheeky questions on the issue of sex-and- drugs-and-rock'n'roll have arrived to tax the recently knighted McCartney. Didi Osman of Birmingham asks: "Hi, Paul - what is the best drug you've ever taken and why?"