According to this note from Christian Stocker on the BitFlux blog, the upload progress meter (using the new file upload hooks introduced in recent PHP versions) has finally been included, officially, into PECL.

After some tweaking, code improvements and remote code execution vulnerability fixes, I finally put the uploadprogress extension into PECL.

Windows users might be out of luck for a while though, since Christian's not pursuing binaries for the package. However, the source is there, and anyone is more than welcome to try...