Sorry, I shouldn't have said that was EU, my mistake. The EU DOES have QGJ as a master sabreist, of course, but the TPM novel, which also says that, is not EU.
The novels are semi-canon. So unless there is ever any better reference made to either QGJ's master and/or sabre skills, that statement pretty much stands.
That will TOTALLY suck if Dooku is QGJ's master. I always imagined QGJ's master with a more mysterious and distant personality than QGJ himself. One other thing, who is QGJ's 1st padawan? Xanatos is 2nd, OB1 is third and Anakin would've been 4th. Who is the mysterious (and fully trained) Jedi that QGJ sucessfully taught before OB1? I'd like to say Mace Windu, but that is unlikely, since they don't seem very close.