I've always had a problem with Research In Motion (NASDAQ:RIMM). Here's a company that people have been valuing at 40 to 50 times earnings, but its moat is so narrow, you could spit across it. Yes, the "CrackBerry" handhelds are very popular. You don't have to tell me how much the "I'm connected!" set enjoys them. I see the squinting thumb-crampers pecking out emails on the train every day.

No, the problem has always been the answer to this question: What does RIM have that can't or won't be offered by bigger, richer competitors, such as Microsoft (NASDAQ:MSFT), Palm (NASDAQ:PALM), Nokia (NYSE:NOK), or any number of telephone providers?

Not much, I'd argue, and today's Microsoft news has made that suspicion a bit more substantial. Reports out of a phone show, the 3GSM World Congress, in Barcelona offer just a hint of the challenge that RIM will need to face if it hopes to avoid the dustbin of history. The word is that Mr. Softy's licensees, including Hewlett-Packard (NYSE:HPQ), will unveil smartphones running the new version of Windows Mobile, which can handle email, as well as partnerships with cellular providers that will directly challenge RIM's biz. (A Wall Street Journal report on HP today shows just how seriously that company takes this effort, claiming the company will break portable devices into a separate business unit.)

Of course, people have been predicting this situation for years now. But now, finally, it looks as though the time of reckoning has arrived. The Redmond dinosaur may have been late to the game, but as usual, once it catches up, the nimble first movers, like RIM, have to worry about getting squashed.

The trouble is, Microsoft isn't RIM's only worry. RIM's juicy, multifaceted business is in everyone's sights, from hardware makers to service providers. Deals between Mr. Softy and wireless providers such as AT&T's (NYSE:T) Cingular, T-Mobile, Vodafone (NYSE:VOD), and others will offer businesses -- in Europe, for the time being -- the chance to push email to increasingly smarter (and increasingly Windows-enabled) phones from the Microsoft Exchange email infrastructure they already use.

What'll be left for RIM investors when this all shakes out over the next few years? Can RIM win a fight against half a dozen of the worlds hungriest businesses? I doubt it. And I sure wouldn't bet real money on it.

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Palm is a Motley Fool Stock Advisor recommendation.

Seth Jayson is looking forward to his next smartphone. At the time of publication, he had shares of Microsoft but no positions in any other company mentioned. View his stock holdings and Fool profile here. Fool rules are here.