So this is one of the many Mini-ITX motherboards that I have in the house, having played about with a fair few making various small computers for different rooms. This one is a little bit different that most, as you don't need to by an a processor for it - that's included on the motherboard itself. I'll go through all of the different ports available on it and then speak about the type of system that it would be good for.
So again, the first thing with this board is that you don't need to get a processor, benifit to this is that it will save you some money, however it does mean that you also cannot replace it if you want to upgrade in the future. Memory wise, there are two slots and the board can handle a maximum of 4GB of RAM (processor is only 32 bit)- decent enough for most modern computers. There is also 1 PCI slot on the board if you want to extend it further by adding in something like a TV card (I'm saying this because it will really only be a LITE media center that this will be able to handle). In terms of attaching hard drives, there are 2 SATA ports which you should probably use to have one small fast one for your main hard drive (OS etc.) and another one for storing media on.
For such a small board, this one packs a massive punch in terms of external ports that are available for use. There are 2 PS/2 ports for your keyboard and mouse, a built in gigabit ethernet port, VGA and PARALLEL ports and the now standard stereo/line in/microphone ports for audio. On top of this there are also 4 USB2 ports on the back of the board with the possibility of adding in at least another two more in the front of whatever case you put this in.
The main problem with trying to decide whether you would get this board or not, is really looking at what you see yourself using it for. My initial thought when I got it was that it would be great as a media center PC, however, as there is only 1 VGA port on the back, this was ruled out (you would want something with an HDMI). Also, the built in processor limits what you would do as well - yes, it is a 1.8Ghz dual core - but its still a low power Atom, so it isn't going to be able to cope with anything too strenuous. It runs Windows 7 perfectly fine and manages to cope with Office 2010 as well (all done with 3GB RAM) so as a basic 'work' computer it is pretty good. The other use that I am planning on trying out over the next few months with it, is to place it in my kitchen with a small touch screen monitor and use it as a 'kitchen system' that can display recipes and let me watch TV shows while cooking it will handle all of this pretty well and a 802.11 wireless PCI card should make sure that it stays connected to a home network pretty well.
One last note - the processor doesn't have a fan on it - so if you do get it, make sure that your case has both an intake and an exhale fan and proper ventilation all around the box.