What you see posted now will have no bearing on what you're offered later in the year (which I take to mean several months out at least). United does rotate their menus periodically but in general you can expect a beef, chicken, fish and pasta/vegetarian dish. You'll also have the option to pre-order a meal which may or may not be different from what's offered on board. I'd check back in this thread as you get much closer to departure to see what's being offered ex-IAD to at least Europe if nobody posts IAD-CPT/JNB.

But the general rule of thumb is to just eat in the Polaris lounge because the food offerings there are far fresher and definitely nicer than the slop served on board.

-RM