Research in Motion’s stock has been on an incredible run since about the middle of July hitting a 52-week high over $140 back at the beginning of the month, however, is down more than 10% in the last 10 days and analyst are beginning to grumble.

Citigroup’s Daryl Armstrong: Sell Research in Motion ASAP

Armstrong believes that even though the BlackBerry Pearl is selling incredibly well and far better than he expected that it is actually cannibalizing sales of other BlackBerry devices.

We think the Pearl accelerated device replacement and upgrades but the impact on net [customer] additions will be disappointing, he writes. Without a meaningful acceleration of subscriber net additions, RIMM becomes more like a traditional handset company. This makes it harder to justify the premium multiple that RIMM currently enjoys over other handset players. Therefore, we recommend that investors take profits right now.

QVM Research analyst Richard Shaw: I love my BlackBerry but not Research in Motion stock

Shaw sees these problems with the BlackBerry maker:

• The stock is down 10.5% from its 52-week high reached on November 24 [10 trading days ago].

• 3 downgrades were issued in the past 30 days [current consensus is 2.4 on 1-5 scale]

• A new patent infringement lawsuit was filed

• They are experiencing difficulty filing restated Q2 results due to investigation of possible stock option grant problems

• They may be about to experience expense ratio pressures to support the push into consumer markets with the new Pearl

• The Pearl appears to be cannibalizing existing BlackBerrys [60% to 70% of Pearl sales replacing other BlackBerrys] resulting in growth of subscriber access fees lagging hardware sales growth

• Major companies with deep marketing pockets are entering the consumer side of the smartphone market [particularly Motorola (MOT), Samsung and Nokia (NOK)], creating substantially greater competition in the consumer market than RIMM has experienced in the enterprise market.

• Microsoft’s (MSFT) push to the enterprise market for Win Mobile smartphones that work with its Exchange Servers will increase pressure on RIMM in the enterprise market too.

I am definitely no expert, however, I can see RIM’s stock falling back a bit until around the time that the BlackBerry 8800 is released. When that happens I think that you will still see a lot of existing BlackBerry users upgrading as compared to net new subscribers, however, RIM makes most of it’s money on hardware sales all indications point to the BlackBerry 8800 outselling the BlackBerry Pearl.

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