I don't think she's beautiful but she is pretty. Unfortunately, she is not a naturally pretty woman. I grew up watching music videos on MTV and I can tell that she got a nose job. Of course, most celebs don't like to admit to plastic surgery.
Oh wow thank you so much for the llama badge! Going through your work I've noticed you have a very pronounced style that is very unique. It's so cool how you have this same style throughout. Great job on this one and awesome artworks!
On first impressions, I really wasn't sure what to think, because the portrait seemed to tell me that Beyoncé had incredibly fair skin, which I know really isn't the case.
However, I believe I've found your reference photo (or at least something VERY close) and now I can see that she, more or less, has a wonderful tan rather than being really dark-skinned.
With all that out of the way, allow me to say you've captured her details perfectly; the bright smile, the chocolate-brown eyes and her incredible hair. Even the smaller things like the facial muscles and the eyelashes look very professionally done.
If I really, REALLY have to nitpick, I'd have probably darkened her skin just that little bit extra, because my first impression; and maybe some will agree with me, some won't, was that Beyonce was very fair-skinned: which isn't really that true.
(For the record, I can't really draw for shit. )
Other than that, you've captured her face extremely well and it is one amazing portrait of an undeniably successful woman. I firmly believe this will go down as one of your finest works... congratulations!