FX 8320 is the only AMD chip I would recommend. Honestly, not many devices are 3.0usb, and you won't probably notice much going to the newer sata either. Your PCI-E is still plenty for any GPU on the market right now. I would get a quality heatsink, overclock your 920, if you haven't already, and call it good till broadwell. It really isn't worth the cost to make the switch just for some extra features as you will need a new motherboard and probably a new copy of windows too.
If you're going to switch, from what you have the only thing I would consider is an AMD 8350. Pair this with a nice motherboard like an Asus Sabertooth 990fx and you'll have a nice setup, but honestly for you I would simply hold off on the upgrades. You'll see very little real world difference from getting SATA 3, or PCIE 3. USB 3.0 is a nice boost if you have USB 3.0 devices but not worth the upgrade for that sole reason. I would keep your current system awhile longer.
An Asus M5A97 R2 and an 8320 will give you some nice overclocking potential, or an 8350 and an M5A97 R2 LE if you won't be overclocking. The new features are really not that much better, the 920 is still good, I would overclock it and wait like previously suggested.
My other motivation for this is that I am building my wife a basic gaming computer from mostly spare parts.
I thought rather than buy an entry level mobo/cpu for her I would get my self the new one and recycle the i7 to her.
If you overclock that I7 920 to around 3.5 GHz you will have comparable performance to an FX8320/FX8350. There is a benchmark here at Toms showing that on a 3Gbs port you can achieve around 260 MB/S and on a 6Gbs - 490/500, which might sound as a huge difference, but is not that of an impact during daily usage. For me it is a waste to "upgrade" to a AM3+ platform now, since you will gain only marginal performance from the CPU side of things, and you will lose some RAM bandwidth and combined with few % worse PCIe video card performance.
On a side note - DDR4 is hitting the market at the end of the year. Why not wait until then?
Thanks for the answers guys. I am going to hold out till later this year for an upgrade for my self if DDR4 is on the way this year.
I will just have to live with seeing that low windows system rating for a while.
For the wifes PC I have been waiting for a decent deal on a CPU/Mobo combo on the newegg shellshocker. Its not going to be a high end gaming machine, mostly will be used to play a lot of free to play games, and some PC gaming classics.
I have been very impressed by how good the longevity of the i7 920 has been. The CPU was never my shortfall it was the Mobo and its lack of more modern features (like usb boot)
I don't even think I have hit 100% on that CPU since I have had it.