The 570 has a slew of features, even though it's only the midrange board. Some of the following that stuck out the most to me are the HD audio in the form of the Realtek ALC883 codec. I won't be leaving my SoundBlaster X-Fi Elite Pro anytime soon, but for people without a soundcard, this is sure to be quite adequate for most sound needs. It also complies with the Azalia 1.0 specifications.
The board is also Vista-ready in that it can support up to 8GB RAM; finally a step up from the 4GB limit seen on the nForce3 and 4 boards. While there is no pressing need now for gamers and "regular" power users to have over 2GB, people requiring lots of RAM for video editing and the like should be more than pleased with the upgrade options afforded by the K9N SLI Platinum.
MSI K9N nForce 570 SLI Platinum
The included D-bracket that fits into a PCI slot opening on the back of the case is actually a very nice feature. It has LED lights that display various codes/formations when there are problems during post. If anyone has used an EPoX board in the past or currently, it is similar to the LEDs they have right on the motherboard that display various codes when/if problems arise. MSI's implementation is nice, though a bit hard to use being that it's on the back of the case.
Another nice addition that when used begs the question of "Why the hell wasn't this done a long time ago?" is the CMOS clear button. No more annoying jumpers...just push this button for 10 seconds to ensure the CMOS has been cleared power back on to have a factory fresh BIOS ready to be tweaked again (though not so aggressively this time).
In the LAN department, NVIDIA's DualNet technology has been added, which allows for the dual gigabit Ethernet ports to act as a single 2Gb port. Plus, the FirstPacket technology allows packet prioritizing so that, in theory, one could be downloading torrents and playing an online game and not experience the total bandwidth saturation that BitTorrent normally causes.
MSI also included their Dual CoreCell technology "which focuses on the 4 'Ps' - Performance Precision, Silence Precision, Image Precision and Sound Precision." For much more detailed information, MSI's site has a very nice pictorial guide showcasing all of Dual CoreCell's features.