WINDOWS 10 (DISK IMAGE) IS FINALLY RELEASED!!!
Microsoft state that Windows 7 and 8.1 users can upgrade to Windows 10 seamlessly.
For those who are using XP or Vista, you have to download the disk image from Microsoft.
Previous Windows 10 ISO iamges were uploaded onto Get Into PC, but in the latest release by Microsoft you can select any edition (Home, Pro, N, Enterprise) and any languages.
And I will force installing it on Jodl's PC.
Windows 10 only adds many new features from other systems such as OS X and Linux, but they are not my concern. There are still many unresolved problems such as applying high DPI settings on Retina displays: It is not exactly twice as large. Many old icons are not updated (e.g. Registry Editor). And the windows looks not as good as OS X because of the texts are rendered badly. Microsoft needs to make another font rendering engine in order to make texts look good as in OS X.
So, if you are a Mac user, just stick with your OS X and wait for the new OS X El Capitan. If you are using a non-genuine Windows copy, don't bother searching for keys or activators, get Ubuntu. Upgrade to Windows 10 ONLY IF you are using genuine copies of Windows 7 or 8.1, or if you have already bought a genuine Windows 10 key.