RIM's foray into the consumer-friendly clamshell design with the Pearl Flip is off to a rocky start. According to reports, sales have been "tepid." That's not a word usually associated with BlackBerry phones.The BlackBerry Pearl and BlackBerry Curve are among the top-selling handsets in the United States. Looks like the Flip may not share the same high rankings.

Shares of RIM tanked about 10% Monday with the news of poor sales of the BlackBerry Pearl Flip. The Flip is RIM's first phone to use the clamshell -- or folding -- form factor. Its smartphones have typically been bar-style or monoblock phones. I tested the Flip extensively. It is a BlackBerry through and through, and offers all the same features and functions found on the Pearl, the Curve, and the 8800 series. It has a beautiful screen, a revised OS, and is generally a good phone.

Buyers, however, aren't sold on the device. James Faucette, an analyst with Pacific Crest Securites cited by Reuters, said that sales have been "slightly disappointing." T-Mobile hasn't released official sales figures of the phone, which has only been on sale for a few weeks.

One issue that may be putting people off is the impending arrival of the BlackBerry Bold and the BlackBerry Storm. Each of these devices holds more cache than the Flip, and more appeal to regular business users. The Bold is cut from the same cloth as most BlackBerry smartphones and features a nice, large screen and full QWERTY keyboard for composing messages. The Storm is RIM's first touchscreen device, and it already has people frothing at the mouth in anticipation. There was no such delirium about the Flip, which is being reflected by the less-than-robust sales.

Faucette goes on to suggest that RIM had better be more successful with the Bold and the Storm, less it miss its quarterly results guidance.