1) USB 3 Support.
USB 2.0 has a maximum throughput of 480Mbps (Megabits per second), USB 3.0 is almost ten times faster than USB 2. USB 3 can run at an effective throughput rate of 350MBps (Megabytes per second). USB 2.0 maxes out at about 32MBps. That's faster than the SATA hard drive you are almost certainly using in your PC.

2) Improved desktop speed.
But now, Linux's memory management has been improved so that currently running programs stay on top of the list of active memory pages. Technical benchmarks show that netbook users and other people who run Linux on limited memory systems can except to see a desktop that's up to 50% faster than it's been in the recent past.

3) File system performance improvements.
Recently, Linus Torvalds noted that both Ext3 and Ext4 do "ACL (Access Control List,) checks on any files not owned by the caller, and it does this for every single pathname component that it looks up." That, of course, is a performance hit. So, Torvalds has changed it so that the default behavior is to load the ACLs without any locking.

The net result is that file system reads are now about 3% faster. That may not sound like much, but it's every file read such as when you start up a program; it adds up. People who use the Oracle originated Btrfs file system will see even better performance gains with up to 15% improvements.

4) Improved graphics support.
There are a lot of minor graphic improvements in this release, but the most significant are better support for the Intel i915 and ATI Radeon graphics family. These changes make graphic drivers for both popular set of graphics devices work better in Linux.

5) Better network support.
Like in graphics, the real news is in new support for specific hardware. The change that will matter to most people is that Linux now includes built-in support for Intel's new Wi-Fi 802.11 3200 hardware. 3200 devices and network cards will be available in 2010. While this version doesn't support the just-approved, high-speed 802.11n Wi-Fi standard, by the time the new network equipment is shipping, 802.11n support will be baked in.