A swap atop Twitter for the “new phase”

Twitter’s growth has been impressive this year. It’s particularly impressive given the problems with downtime the micro-messaging service had for several months during the late spring/early summer. If any time seemed ripe for a change at the top of the company, it was then. Instead, Twitter weathered the storm and has had uptime galore recently — and oddly, now it’s making a change at the top.

Twitter chief executive Jack Dorsey is stepping down from that role to become chairman of the board. Current Twitter chairman Ev Williams will take his place, as Williams lays out in a blog post today.

In the tough economic times we are currently facing, a lot of companies are undergoing changes to stay afloat. But as I mentioned, Twitter seems to be thriving, especially amid all the interest in political chatter, and never once in his post does Williams mention the economy or anything like layoffs.

Instead, Williams writes:

We’re entering a new phase now and there are new kinds of challenges ahead. Healthy companies acknowledge the need for change even during the best of times. As Twitter grows both internally and externally, we took a good look at our path forward and saw the need for a focused approach from a single leader.

And Williams, who has led other companies such as Blogger and Odeo, clearly thinks he’s the right man for the job. But Dorsey apparently won’t take on Williams’ former executive role, as chief product officer. So it’s not entirely clear where this leaves Dorsey in terms of the day-to-day of the company. It would seem he’s taking a big step back.

Williams’ post really doesn’t say much as to why this switch is happening now, so I won’t speculate. We’ve contacted Twitter for that information and will update when we hear back.

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