As many others, I recently downloaded Windows 7 build 7100 as it became available from Redmond earlier this week with the intent to slap it on my EEE 901.
First issue was to get it installed without a DVD drive. The simple solution was to create a bootable USB drive and copy the installation files to it. A good guide is available at http://www.intowindows.com/how-to-install-windows-7vista-from-usb-drive-detailed-100-working-guide/, but I never managed to get my 8 GB USB drive to boot so I installed Windows 7 from within Windows XP. That worked without a hitch, after a few restarts.
However, the second issue I ran into was that the screen was black after it had booted up. To get around the black screen, I pushed the power button for a second (or two) to get it into sleep mode, then pushed it again to resume. That trick made the screen come back. The problem seems to be between the BIOS and the ACPI driver. Furthermore, I got a few alert messages, “Missing Audio Driver”, “Missing VGA Driver” and “igfxext.exe not running”. Heading over to http://gecko.me/?acpifix provided me with a means to solve the missing driver messages. The guys over at eeeuser.com solved the last problem with igfxext.exe, the solution is in http://forum.eeeuser.com/viewtopic.php?id=62614