I suspect the Microsoft servers will be swamped on July 29. There seems to be a plan to roll it out in stages and those who have reserved a copy early will find it downloads with updates and it will be available to install when they're ready.

Nick, I have a touch screen laptop, the environment that Windows 8 was developed for. A disconnect for Win8 was how few people paired it with touch devices. What kind of device/s are you using Win10 on, and does it retain some accommodation for touch screen computers? That is the device (with the Pro version) that I would probably opt first to test upgrade. Microsoft is pushing like programs out to users - Home version users of 7 or 8, etc., get Home version of 10. I use Win7 Ultimate on my desktop and am happy with it, so would probably delay an upgrade till near the end of the free offer period (let other people work out the bugs!).

It's clear this free upgrade is Microsoft's attempt to hold onto market share. People unhappy with Win8 flavors can get rid of it, and others will go along for the ride. In particular, they're up against the Android OS. The Win8 release will go into the dust bin along with Windows ME, Windows Vista, and illustrates something that other companies learned about shocking users with something so radically different. MicroPro Wordstar used to be a powerful word processing program, but when they released Wordstar2000 it didn't work the same and they scared off most of their users and never regained market share. Ironically, Microsoft stepped in with Office Word to take over that market.