In recent usage, the phrase signing statement has referred mostly to statements relating to constitutional matters that direct executive agencies to apply the law according to the president's interpretation of the Constitution.
You might need to exercise a little bit more patience. Though Microsoft (MSFT, Tech30) said a month ago that Windows 10 would become available on July 29, Microsoft clarified on Thursday that everyone won't be able to upgrade on that day. Microsoft will roll-out upgrades slowly, in waves.
Perhaps it is a testament to Microsoft's legacy that some popular applications that date from the late 1990s can still run on its latest OS, Windows 10. The operating system, which will launch on Wednesday 29 July, has already been tested (and been seen running) on some very, very old and very, very slow hardware.