To quote: A complete new version of PS3 Multi Tools for Windows is released! The new version is now called PS3 Multi Tools for Win & Mac... why? Read!

Here are the changelogs from v2.5 to v3.0 (7, XP , Vista & Mac):

You can now search minor/security updates for PS3 Multi Tools for Windows v3.X.X
Complete new XMB design
Now running on Mac OS X Snow Leopard
Offcial Firmware 3.41, 3.55 & 3.66 added
Package signing fixed (Not working on Mac)
Kmeaw 3.55 CFW added
Detailed game description will be shown
Added CFW355-OTHEROS++-SPECIAL Custom Firmware
Added more Homebrew:
- OpenPS3FTP always the newest version (Kmeaw & Geohot)
- QA Flagging Tools: flag, reset flag & extra flag
New Settings added: Show MD5 Hashes

Additional changelogs only for Windows 7 Users:

Added more Taskbar icons
- Download latest version of MultiMAN
- Load news
- Search updates

Requirements for Windows 7:

.Net Framework 4.0

Requirements for Windows Vista & XP:

.Net Framework 2.0

Requirements for Mac OS X Snow Leopard:

Wine with .Net Framework 2.0 OR Crossover with Runtime: .Net Framework 2.