Yip we have many users affected, according to MSOL service health page:

Exchange Online

Incident EX3022
Incident start time: Apr 23, 2013 8:30 AM
Date and time	Status	Details
Apr 23, 2013 9:05 AM	Investigating	We are investigating a service alert. At this time we don't have enough information to identify whether this is an actual service incident. We will provide more information shortly.

From: nznog-bounces@list.waikato.ac.nz [mailto:nznog-bounces@list.waikato.ac.nz] On Behalf Of Daniel Siva
Sent: Tuesday, 23 April 2013 9:40 a.m.
To: nznog@list.waikato.ac.nz
Subject: [nznog] Office 365 Hong Kong issue?

Hi all,

Is anyone noticing issues connecting to mailboxes at their Hong Kong DC?

We have users spread between Singapore & Hong Kong, most of the users on hkxprd0310.outlook.com cannot connect.

We have been on hold to M$ for awhile now, & would just like to know if anyone else has any feedback...

Cheers!

- Daniel