The Twitter status blog reports this morning that several key services have been taken offline, including IM:

"User account restoration and deletion is currently disabled. We expect these services to be brought back tomorrow afternoon.

In addition, IM is still offline as we work to bring it back in a more stable form. The API rate limit remains at 30 requests per hour.

Some users are still reporting some timeline inconsistency issues and we’re working to track those down."

The blog doesn't specifically mention the Apple WWDC in San Francisco, but another company blog confirmed yesterday that engineers have been taking steps to handle today's increased WWDC load, including "utilizing more memcache, employing more read-slave servers, and by fixing some bugs for improved efficiency."

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