Windows SharePoint Services V3 and Microsoft Office SharePoint Server 2007 are now be able to get updated to the latest available bits with April CU.

Side Notes:
The sizes of the packages are smaller than in the past (June 2010 CU and earlier). This is because you need to have SP2 installed so that not all fixes between SP1 and SP2 are necessary to ship with each CU.

KB articles are having sometimes a bit delay but the link should work when these are available.

WSS:

2512783 The full server package for WSS
http://support.microsoft.com/default.aspx?scid=kb;EN-US;2512783

MOSS:

2512782 The full server package for MOSS
http://support.microsoft.com/default.aspx?scid=kb;EN-US;2512782

Download and installation information:

After applying the preceding updates, run the SharePoint Products and Technologies Configuration Wizard or “psconfig –cmd upgrade –inplace b2b -wait” in command line. This needs to be done on every server in the farm with SharePoint installed.