Because there was such a high demand Microsoft removed the download limit for the Windows 7 beta. You will be able to download the beta for another two weeks (until January 24th by now).
The current requirements to install the beta are:
- 1 GHz 32-bit or 64-bit processor
- 1GB of system memory
- 16 GB of available disk space
- Support for DirectX 9 graphics with 128 MB memory (to enable the Aero theme)
The requirements will probably change sooner or later but right now feel free to install the beta on an old PC. Although Microsoft offers localized editions (Arabic, German; Hindi, Japanese aside from English) there are many untranslated parts.
I have been able to try Windows 7 already. For me, as a Vista user, the GUI is very familiar, but it’s great to see the new features in action. You can now preview tabs on the taskbar, resize windows by dragging it to the top or left/right of the desktop or take screenshots ten times faster than before. The new paint is a really cool tool now, but I don’t want to spoil the fun for you, just try it!