Seattle - Amazon will start shipping its Fire tablet today, a day earlier than planned.

The online seller is also bumping up the ship dates on its new Kindle Touch and Touch 3G, shipping these devices on Nov. 15 -- six days earlier than announced.

Amazon did not give a reason for the early shipments. The company reported the $199 Kindle Fire is the best-selling item on Amazon.com since it became available for pre-order in September, and it is now building millions of additional units, said Dave Limp, Amazon Kindle VP.

The Fire's competitor, the Barnes & Noble's Nook Tablet, is slated to ship on or about Nov 17.