for me the handwriting recognition seems to be pretty accurate. I definitely see its being beneficial for someone who would prefer to quickly jot down a note rather than one or two finger type things out. That being said like the OP said, I've only ever really used it out of boredom, simply because its not how I use my Surface Pro.
Its not something I am going to be using much either. I do think there is a sub-set of users that would want to have this feature. Going forward, Microsoft needs to have this technology fully fleshed out I think.
Gee, I have started using it quite a bit. Especially in meetings writing comments on open Word docs. It is really a valuable process much like I used to do on paper agendas, etc. I do have to make sure my printing is clear to make use of the notes later but I am blessed with nice handwriting so not much to change other than the occasional "eraser" move when I screw up.
I have found this feature useful when using the Surface Pro with the type cover/touch cover folded back (so using it in a true "tablet" mode). In this mode you can of course use the on-screen keyboards vs writing. I have found the writing to be smooth and the handwriting recognition to be exceptional, despite my poor form. I find this actually easier than the on-screen keyboard. This is particularly useful when using an app like OneNote and you want to make some drawings and then enter text, it is much easier to keep the pen in your hand and alternate between drawing on the page and then writing in the handwriting recognition area. One downside to the writing recognition though is that it uses common words to "guess" what you are writing, so if you are using nonstandard words (in my case scientific terms), then it does not recognize them unless you add each one to the dictionary which is quite cumbersome. So for specialized text the keyboard options are much better.