Unbeatable Photoshop CS3 Integration:
Open files in Photoshop as Smart Objects. (This way you can tweak your Lightroom adjustments within Photoshop just by double-clicking the Smart Object layer that contains your raw file.)
Select multiple images to merge as a panorama
Merge multiple exposures into a single Photoshop HDR image
Load multiple files (or virtual copies of a single file) into Photoshop as separate layers in a single document
Selective image editing that rocks:
Lightroom 2 adds a Retouch tool right within the Develop module (see screenshot). That means you can paint regions of the image to dodge, burn, saturate/desaturate, adjust contrast, and more. Edits are stored as metadata, just as all other LR adjustments are stored, and are applied directly to your raw images. (Because people will quickly ask, I'll point out that unlike Apple's newly released Aperture 2.1, Lightroom integrates its selective editing tools right in with the other adjustment tools. In Lightroom you don't have to generate a TIFF file for editing, and unlike in Aperture, you can always tweak the results later. In addition, Lightroom features Auto Mask technology for tweaking the clicked region without bleeding into neighboring areas.)
Other goodness:
Library Module:
Streamlined Library layout
Smart Collections (based on search criteria)
Powerful Filter Bar to search and refine images
Suggested Keywords for simplified keywording
10,000 pixel size limit raised to 30,000 pixels
Output-based collections
Multiple monitor support:
Four flexible modes for an alternate window: Grid, Loupe, Compare, Survey
Live Loupe mode
Export functionality:
Auto-add exported images to the Lightroom catalog
Auto Output Sharpening for images on export
Develop Module:
Non-Destructive Localized Correction for dodging and burning specific areas of an image
Post-Crop Vignette
Basic Panel Keyboard Shortcuts
Improved Auto Adjustment
Improved memory handling through 64-bit support on OS X 10.5 and Vista 64-bit.(Not limited to develop module)
Print Module:
Picture Package for multi-page layouts
Print Module output directly to JPEG
Enhanced Print Sharpening based on PhotoKit Sharpener algorithms
16-bit Printing for Mac OS X 10.5