Microsoft has removed restrictions that prevented non-invitees from downloading Vista's First service pack release candidate.
6001.17128.080101-1935 v.774 as it is affectionately known contains a number of bug that testers had previously encountered in pre-release versions of SP1.
The release candidate installation is not without quirks though as Mary Jo Foley of ZDnet.com reports as it requires the un-installation of previous SP1 packages and will cause your computer to reboot several times.
It also expires on the 30th of June 2008 although one can expect Vista's SP1 gold version to be available at that date.
As for most non-officially released code, Microsoft warned that this Release candidate "does not recommend installing this software on primary or mission-critical systems".
APCmag also revealed that Vista SP1 will come with an important addition - DirectX 10.1 - which will make all but the most recent ATI graphics cards obsolete overnight.
Nvidia has no plans to release a DirectX 10.1 compatible part for now and instead is focusing on DirectX 11, which has yet to be announced.
However, it remains to be seen how far the gaming community will adopt the new DirectX implementation.