When I tried XBMC about a year ago, there were numerous problems. There was problems with the packages not working with the most recent version of Ubuntu. After the install, there was random seg faults throughout the UI, involving everything from playing video to navigating the UI to indexing video files. There was also the huge issue of it not recognizing more than 75% of my library, and then the 25% of the library that it did "recognize", it mislabeled about 75% of that as well. So then there is the issue of the content that it did correctly identify (about 10% of my library) alot of that content would not render using their playing tool. After about a day of playing with it, I uninstalled it. I tried another solution called "Boxee" and found the same class of problems exist with it too.
I will say that in the span of two days I wrote an indexer to scan my 20TB library, put the files into a mysql database, and then wrote a front end for it (all in PHP), which then I can use to one-click pop mplayer fullscreen (in -slave mode), and it also does the same with Youtube videos (using Chrome with fullscreen options, and youtube-dl to queue / download the video files and add them to my library). It has a lot of other features, but I will say that is a lot faster to find my actual content, and does not attempt to mislabel anything, and in the end I have a pretty scalable solution.