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.
Microsoft this week announced that the Windows 10 release date is July 29th, and it also pushed out the Windows 10 upgrade app to all Windows 7 and Windows 8.1 users. This utility allows you to reserve your Windows 10 upgrade. But first, you might want to check if your computer can run the upgrade.