The rumors have been around for years at this point and today there is no short of an upcoming tablet. The rumor comes from Scott Moritz of [The Street]. Apparently Apple is planning a deal with Verizon to help subsidize a Tablet mac. This means you would sign up for a Verizon data plan and get the tablet at a reduced rate.
"The device, designed as a larger version of the iPod Touch, will have a 9-inch to 10-inch touchscreen and possibly a keyboard, as analysts, industry sources and news reports have outlined."
We should know around September if this rumor is true as the prediction here is that a holiday release is imminent.