IBM released today the FP1 for Lotus Notes/Domino 8.5.1.

The fixpack included support for Notes on Windows 7 and Snow Leopard (Mac OS X 10.6.2).

Additional information about this Fix Pack, including a list of fixes, is available in the Notes/Domino 8.5.1 Fix Pack 1 Release Notice.

The IBM Technote 4025721 provides download information for IBM Lotus Notes and Domino 8.5.1  Fix Pack 1:

A list of fixes can be found here.