If you’re not already using the VLC Media Player I highly recommend it. First and most important it has a great security track record (it’s open source!) Second it’s bundled with just about all the codecs you’ll ever need (forget downloading DivX etc separately). Last, it’s multi platform!
0.9.9 has just been released and no security issues were addressed (actually a good or bad sign depending how you look at it)
Biggest highlights:
- Improved Intel-based Mac performance
- New decoder included for Real Video — however, how popular is real these days?