Research In Motion today promoted yet another sale of its PlayBook Tablet. The PlayBook has been available for less than the $499 retail price on and off since September. The last promotion ended December 31, but less than two weeks later RIM put the tablet back on sale.

Anyone business looking to purchase the 16GB, 32GB, or 64GB PlayBook can pick one up for $299 between January 9 and February 4. RIM is offering this reduced pricing via a number of vendors, including CDW, CompuCom, PC Mall, PC Connection, Insight, Softchoice, Zones, and several others.

RIM is offering even steeper discounts to businesses that want to order more than 100 PlayBooks.

The PlayBook still doesn't have access to corporate email, calendar, and contacts on the device without the assistance of a tethered BlackBerry. Though RIM has made decent progress on PlayBook OS 2.0--which includes email, etc.--the revised system software isn't expected to ship until the end of February.

InformationWeek's Fritz Nelson took a long look at PlayBook OS 2.0. You can read more about it here.

The lack of email makes the PlayBook a questionable purchase at the moment. Though updated software is on the way, and email can be added via a BlackBerry, every other tablet in the market has email available out of the box.

Also, this latest sale may be a last-ditch effort by RIM to clean out whatever stock of PlayBooks is left before new models arrive later this year.

[ What's the next step for RIM? Read Samsung Doesn't Want RIM. What's Next? ]

A roadmap leaked earlier this week suggests that RIM is working on not one, but two, new tablet computers.

The first device is being called the "3G+ PlayBook" and will reportedly become available in April with a seven-inch display. This device will be an upgraded version of the current model, though specific improvements weren't detailed. The second device will have a 10-inch display and will support Long Term Evolution 4G. It is due to arrive in December.

An April arrival of an upgraded seven-inch PlayBook makes sense, as that will mark one year from the launch of the original PlayBook. The original PlayBook launched with support only for Wi-Fi. It was supposed to gain LTE 4G support and WiMax support by September 2011. It never did, and Sprint and Verizon Wireless eventually canned plans to sell such a device. It looks like RIM decided against adding those elements to the current hardware.

If you're in the market for a bargain buy, contact RIM or one of its retail vendors, though I'd highly suggest waiting or looking at other tablets instead.

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