I am actually happy now that I look at my picture from 2009-2010 and then the 2010-2011 progression. I've gotten better with details, anatomy, and colouring in general. Even my human and anime art has gotten better. I noted that as I improve with them (which i enjoy) my furry art kind of goes downwards (i don't enjoy it as much so I guess i am not trying as hard)
Take a look at your art from this month, then six months ago, then this time last year. See if you feel the same way. If it all looks the same, either you're an amazing artist, or you've maxed out your level of improvement.
I hope everyones end of the year goes well, and next year