With Windows 7 the promise is that the next iteration of the Windows client will be superior to its precursor in every aspect. This is also valid for the performance delivered by Windows Search or the indexer. Chris McConnell, a principal SDE on the Find and Organize team, revealed that Microsoft had optimized the Windows 7 indexer in order to offer boosted performance and reliability compared to Windows Vista, which offers the same in comparison to Windows XP.
In Vista "the indexer runs as a system service vs. as a per user process," McConnell explained. "This minimizes impact on multi-user scenarios e.g. only one catalog per system results in reduction in catalog size and prevents re-indexing of the same content over and over. Additional benefit is gained from the robust nature of services. The indexer employs low priority I/O to minimize impact of indexing on responsiveness of PC. Before Windows Vista, all I/O was treated equally."