Despite being part of the AVCHD official consortium, Adobe has no plans to include support for the AVCHD codec. After emailing Adobe on this issue, they responded with “Unfortunately, there is no information yet regarding your concern. From time to time, please visit our website for more details.”
AVCHD is becoming more common on new hard drive-based cameras, and is supported by some other video editing packages such as Apple’s iMovie08. Adobe Premiere has been an industry standard video editing application for some time now, however disappointments like this will lead to many developers looking for other solutions.