RIM has said it will launch the tablet in the U.S. in the first calendar quarter of 2011. But in its quarterly earnings call, executives said they don't expect to record revenue from the PlayBook until the first quarter of the company's fiscal year, which starts in March.

RIM is forecasting revenue of US$5.5 billion to $5.7 billion for its fiscal fourth quarter ending in February, but that will not include revenue from the PlayBook, said Adele Ebbs, RIM's vice president of investor relations, during a conference call to discuss the company's quarterly earnings.

A RIM spokeswoman said later that no date has been announced for the launch of the tablet.

"The PlayBook redefines what a tablet should do," RIM co-CEO Jim Balsillie said during the call. He said the excitement from customers has been "overwhelming" and that the PlayBook will have an edge over competitors because of the ease of running existing Web apps on it.

The PlayBook faces tough competition from the popular Apple iPad, however, which some enterprises have already started using.