http://www.appleinsider.com/articles/08/07/29/photoshop_lightroom_2_released_as_adobes_first_64_bit_mac_app.html
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Following an earlier open beta, Adobe on Tuesday released version 2.0 of its Photoshop Lightroom post production photography software, which stands as the company's first application to run 64-bit-native on Apple's Mac OS X Leopard operating system