Is the Z10 BlackBerry's savior? Not so fast.

Bad news on Q1 results sends BlackBerry stock tumbling in trading on Friday. 

It was supposed to be a major do-over: a new name (BlackBerry, instead of RIM), a new operating system (BlackBerry 10), and the sleek and stylish new Z10 handset.

But in a conference call with investors this week, BlackBerry announced that it had sold only 6.8 million smart phones in the first fiscal quarter of this year, with 2.7 million of that number consisting of BB10 devices. That missed predictions from many analysts, who had predicted BlackBerry might sell a total of 7.5 million smart phones in Q1 (including 3.6 million BB10 units), according to Bloomberg BusinessWeek. 

As a result, BlackBerry stock tumbled on Friday by as much as 26 percent. 

For its part, BlackBerry execs have said the company is only in the "early stages" of a wider roll-out that will take place over the remainder of 2013. But Kevin C. Tofel of GigaOM, for one, isn't having it. 

"I agree it is early for BlackBerry yet, but I don’t think sales of the new BlackBerry 10 devices are meeting or exceeding expectations," writes Mr. Tofel. "For one thing, I really anticipated that the loyal BlackBerry fans would be more receptive to the new phones and software. This group should be the company’s bread and butter for sales. I’ll grant that the new devices aren’t yet available in every market, which could be part of the issue." 

The Z10 received largely favorable – if not quite ecstatic – reviews when it launched earlier this year, although many critics questioned whether BlackBerry had done enough to attract non-business users. 

"At $199 (which BlackBerry says is the suggested on-contract price in the US), the Z10 and BB10 are a nice piece of kit," wrote Tim Stevens of Engadget. "The BlackBerry faithful who've been waiting patiently for something more modern will flock to this (and its QWERTY-having cousin) in droves, but there simply isn't enough here to woo those consumers who have already made investments in Android or iOS. Too little? Maybe. Too late? Sadly." 

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