Intel's NUC targets digital kiosks but most of us would probably agree that a nice home theater PC (HTPC) would be something that it could be used as. It could also make a nice system for children that could be introductory. One drawback when it comes to the NUC is its Sandy Bridge chip: it is last-gen tech that gives you Intel's HD 3000. It would be safe to presume that a version with HD 4000 GPU is coming out after this one.
Dimensions of 10x10cm make this unit one of the smallest there is out there, with its only competitor (x86 competitor) hailing from VIA, which has made units as small as 6X6cm, the Mobile-ITX is one good example of how small VIA can go. You may think that the small size of these motherboards is beneficial, but they only handle weak VIA CPUs that are very slow, so they are mainly targeted towards installations of low power. A Core i5 processor in a form factor like 10X10cm is impressive, making Intel's unit both small and powerful.
So what about the Raspberry Pi? Well, at 8.5x5.5cm, the Pi stands a bit smaller than the NUC. It's also probably thinner as well, as it is 2cm deep. The Raspberry Pi also has a larger number of outputs and inputs but Intel's NUC has mini PCle connectors that enable it to add most functionalities. Raspberry Pi's 700MHZ ARM SoC are completely obliterated by NUC's Core i3 and i5 processors when it comes to processing power. Another advantage of the NUC is the fact that its users will be able to use the large x86 software ecosystem (Windows) without any hiccups. The users will also find it easier to develop software, because making software for the NUC will be equivalent to making software for a standard. Raspberry Pi doesn't have these two very important perks.
Price-wise, the NUC won't be expensive; it probably won't be as cheap as the Pi (it goes for $25) but it will probably be within a reasonable price range, somewhere around $100. The NUC will possibly come with a pre-installed CPU and maybe even some RAM, judging from the heatsink's presence.
So there you have it, Intel NUC is sure to shake the mini-computer industry once it's released, watch out Raspberry Pi!