New feature: Leopard support
Complete rewrite for Mac OS X 10.5 Leopard

New feature: All-in-one interface
Results are shown next to the search query

New feature: Live editing of queries
You may change criteria without stopping the running query

New feature: Exclude files by location
Alongside a scope for the search you may define a list of places to ignore

New feature: Limit output by attribute
E.g. show only the 100 most recently modified files

New feature: Unlimited customizability of result columns
Show and sort by any attribute you can think of

New feature: Enhanced Preview
Preview files using Apple's QuickLook

New feature: Copy-paste support: text
You can copy from the result list to your favorite text editor or spreadsheet

New feature: Copy-paste support: text
You can copy from the Inspector to your favorite text editor or spreadsheet

New feature: Copy-paste support: files
You can copy files (cmd-shift-C) from the result list to paste in the Finder

New feature: Copy, Move, Alias
With HoudahSpot 2 you may copy, move or alias found files: Great for housekeeping

Enhancement: Customizable global shortcuts
Frequently requested enhancement