From the BlackBerry DevCon Asia site:
Important Notice: due to the current high levels of flooding in Bangkok, Research In Motion® (RIM®) has decided BlackBerry® DevCon Asia will not take place in Bangkok this year. The decision was made following advisories that warn of ongoing dangers related to the serious impact of rain and floods on the local infrastructure in Bangkok, where the conference was scheduled to take place. The safety of attendees at any BlackBerry event is of utmost importance to RIM.We will keep you updated as details become available. Are you attending BlackBerry DevCon Asia, and if so, how is this affecting you?
RIM is committed to the developer community in Asia and we are currently evaluating new locations and possibly new dates for the conference. Further details will be communicated in the coming days. We regret not being able to hold the conference in Bangkok this year, but we look forward to returning the event to Bangkok in the future.
RIM apologizes to all current registrants for the late notice and inconvenience this may have caused, but appreciates their understanding due to the unforeseen circumstances that Bangkok is currently suffering. Existing registrations will remain active pending confirmation of the location and timing for the BlackBerry DevCon Asia event. Questions should be directed to devcon@rim.com