Due to recent glibc and gcc upgrades, we figured it'd be best to rebuild the whole core repo off the new toolchain, to take advantage of the latest-and-greatest changes.
Daniel has taken up this task, rebuilt all packages for both architectures, and moved them to [testing].
If you run into any problems, please report them on the bug tracker.
Update: All packages from the core rebuild were moved from [testing] to [core].