4) Staging Drivers
Did you ever want to use a device for Linux where there was 'some' support for it, but it wasn't good enough to be in the main kernel? If you use a lot of new hardware, you've probably been there. As Jake Edge reports, "There has been an ongoing struggle between those who want to see drivers get included as quickly as possible versus those who want to see them approach or attain normal kernel quality levels first." He's got that right.
Greg Kroah-Hartman, who has been leading Linux hackers' efforts to create drivers, created the -staging tree for these, not quite ready for prime-time drivers. You don't have to use them, but they're available if you need them. For example, I wanted access to USB/IP. This driver enables you to access USB devices over a TCP/IP network. I'm using it to access printers that are attached to a Belkin Network USB Hub. Is it perfect? No. But it does let me get to those printers, so that's a win in my book.
5) Network improvements
The 2.6.28 kernel includes new support for UWB (Ultra Wide Band), Wireless USB, UWB-IP, and Nokia's mobile phone Phonet Network Protocol. That's all well and good, but unless you're one of the few who work with UWB or Phonet, I'm not sure how important that will be. I do think Wireless USB will end up being a big deal. That said, what I think is easily the neatest improvement in 2.6.28's networking is that it now supports the minstrel Wi-Fi rate control.
Chances are you haven't heard about minstrel. Once you have it on your Wi-Fi equipped computer though you'll wonder how you ever lived without it. Minstrel keeps a constant watch on which Wi-Fi AP (access points) in your area are delivering the fastest possible performance and automatically hook you up with it. With minstrel, you're pretty much guaranteed to always get the best Wi-Fi connection that's available. I like this. I like this a lot. Frankly, based on what I've been seeing while using it with my Linux-powered ThinkPad R61, I'd upgrade to 2.6.28 for this feature alone.
So, my advice to you is that if any of this sounds good, you can either upgrade your PC to Linux 2.6.28 manually, which is what I did, or you can start encouraging your favorite Linux distribution group to move to 2.6.28 sooner rather than later. You'll be pleased you did.