Dave Helmly has a text and video intro to PremierePro and P2 support: "With the new Premiere Pro CS3 and the 3.1 update , you can now natively Ingest, Edit, and Export the Panasonic P2 format. All you need to do is to shoot your video and simply drag, drop, and edit – it’s that easy. There is no need to transcode your video with an intermediate codec in order to use them on the timeline, and there are no AVI or Quicktime wrappers – just native P2 format." (originally posted 10/9/07)
Update: The 3.1 upgrade is only available in Help>Update as of 10-18-07. Some people who installed the CS3 beta are Not Getting Adobe Production Premium Updates automatically.
Premiere seems to only support P2 MXF, not AVC files (though there is the Elecard Converter Studio AVC Edition to convert AVCHD to HDV). According to Rod Harlan, the 3.1 upgrade "WILL support DVCPRO and DVCPROHD at all the frame rates and resolutions that the camera can create." There's more in Premiere's LiveDocs, and more on HD in general in this blog post Premiere Pro: more partners.
Meanwhile there's Final Cut Pro 6.0.1, now with AVCHD support. Oliver Peters noted that there should be yet another release soon: "AVC-I support in FCP was shown at IBC and will be in a release after Leopard ships. It may require a transcode to ProRes."
Dave Helmley adds info on AE: "The After Effects team officially announced support for Panasonic P2/MXF format at the IBC show in September. They are currently working on the next update for AE and it will include P2 support. They are planning to release the update [also for Apple's OS X Leopard -ry] before the end of the year. I am currently working on a new short video, which will show After Effects CS3 working with P2 footage."