The three-day blackout interrupted email and Internet services for tens of millions of frustrated users and inflicted more damage on an already tarnished brand.

I've been a pretty big BlackBerry advocate, said Kate Jacobson, a student at Michigan State University. 'But I'm done playing these games with you, BlackBerry.'

After using a BlackBerry for three years, she said the outage was the last straw. When service was restored Thursday morning, she got an iPhone anyway.

Her unhappiness was shared by users across several continents. BlackBerrys in Europe, Asia, Latin America and Africa had been without email or chat messages since Monday.

In the U.S. and Canada, the outage was shorter, starting Wednesday. But many, perhaps most, of the world's 70 million BlackBerry users were affected.

'When I woke up in the morning and had zero emails, I was like, 'That's impossible,' Jacobson said. She had already endured problems with her BlackBerry Curve turning off at the wrong moments. It didn't play videos well, either.

It will take more than an apology to win back some Blackberry users. But RIM's latest fiasco is unlikely to result in a mass exodus of its corporate and government clients.

BlackBerrys, like other imperfect business technologies, are deeply entrenched in commercial settings, and getting rid of them represents time and money that companies may be reluctant to give up.

Indeed, RIM may experience a slower, more subtle migration from its smartphone. Two types of people have kept the BlackBerry from sinking further into the oblivion of once-iconic but forgotten gadgets: corporate IT managers and aspiring young people in developing countries like India. Countries outside North America account for 54 percent of RIM's revenue.

In the April-to-June period of 2010, 19 percent of the smartphones sold in the world were BlackBerrys, while a nearly equal number, 18 percent, were from a variety of brands that use Google Inc.'s Android software, according to research firm Gartner Inc.

In the same three-month period this year, 12 percent of smartphones were BlackBerrys, while Android phones zoomed to 43 percent, outselling BlackBerrys more than three to one.

BlackBerry phones have not kept pace with the iPhone and its imitators, said Shaw Wu, an analyst at Sterne Agee.

A recently launched update of the flagship "Bold" model with the signature BlackBerry keyboard is selling well, he said, but an all-touchscreen model isn't. It just doesn't match up to the iPhone and Android phones.