UPDATE: Ask and you shall receive-ish. Apple has posted a Knowledge Base article detailing (part of?) the problem (via Macrumors):
Symptoms Updated: July 22, 2008, 4 p.m. PDT. On Friday, July 18, 2008 (2008-07-18) we experienced a serious issue with one of our MobileMe mail servers. This issue is currently affecting approximately 1% of MobileMe members. Affected members are unable to send or receive email at www.me.com or access email using any email client software such as Mail on a Mac or Microsoft Outlook on a PC. Products Affected MobileMe Mail Resolution We understand this is a serious issue and apologize for this service interruption. We are working hard to restore your service.
Original post after the break...
MobileMe problems continue to mount, user frustration levels continue to rise, and Apple continues to not realize they're becoming a "big company" and along with scaling infrastructure to support a growing user base, their traditional veil of secrecy won't be tolerated by the larger market they want to play in -- especially the enterprise.
Despite Apple's lack of anything approaching a communication strategy (not only for customers, but apparently for their own front-line support people as well), Apple Insider has managed to glean at least some information about what's going on.
Problem the first: a fiber optic cable was cut during maintenance, and has since been repaired.
Problem the second: a mail server went down on Friday and attempts to bring it up have only resulted in more problems.
While these issues can and will arise (Twitter is newsworthy now when it stays up for a couple of days, Amazon S3 went down for a while over the weekend, cables were cut taking whole regions out earlier in the year, etc.), Apple needs to step up on the customer service end, and with more than just small notices on account pages reading: 1% affected.
Wanna play with the big boys in the cloud, you gotta follow the big boy rules on accountability. If it helps, just think of this as a user experience issue, and slap a shiny interface on the problem reporting and resolution system, b'okay?

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