The new versions of libjpeg and libpng required a rebuild of all dependent packages.
The libjpeg/libpng rebuilds are now complete and are moving from [testing] into the main repos.
Due to the large number of rebuilds required, packages will take a while to propagate to the mirrors. It is advisable to check the state of your mirror before updating (https://www.archlinux.de/?page=MirrorStatus).
Remember to check your unofficial packages (AUR and third party repos) for required rebuilds.