An Update of Aperture 2 is also available since this night (version 2.0.1, 43,9 MB). As usual this improves the performance and general stability plus some fixes of other minor problems (full description available on the web support page given below).
Aperture 2.0.1 addresses issues related to the performance and overall stability of Aperture 2.It also fixes a number of other minor issues; the Aperture 2.0.1 Update is recommended for all Aperture users.
More information at the following web address: http://support.apple.com/kb/HT1083
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