I've recently purchased the upgrade to Adobe Photoshop Lightroom 3 and have been extremely impressed by the performance improvements. On Lightroom 2.7 my catalog with 85,000 photos was very slow to open and even slower to find/filter images even on a PC running Windows Vista 64 with quad core processor and 8Gb of Ram.
Lightroom 3 resolves this and is almost instant to filter photos to various slice and dice criteria.