People are not content to have 5E be a "good" or even "excellent" D&D; they want it to be perfect. Which it will not be. People are looking at 5E and seeing something that they do not like and writing the entire system off. That's not really fair for both 5E and themselves. What if 5E is a great D&D, but a person ignores it because they heard about that something that was "off"? They may be missing out on an awesome game that will do what they want...or not, but there is only one way to find out. But don't write something off without knowing what you are talking about...and internet hyperbole is not the way to find out.
After 5E comes out in its complete form, I am perfectly fine with people saying something along the lines of, "5E is an excellent/good/average/lame system but I prefer
But what I don't want to hear is, "5E is lame because it's not perfect."
-Over at ENWorld, Morrus has an excellent post on the potential look and feel of 5E, specifically "fluff" (descriptions of effects) vs mechanics (what does the effect do from a numbers viewpoint). He does a good of describing the differences in past editions and the conflicts that can arise therein.
Personally, I think you can mix the two. We do not have to go back to the Gygax style of prose or the heavy word count wherein effect is lost. If there is one thing the current writers are good at, it is condensing information down to what is truly needed. They do not use three sentences to describe an effect when one will do. This then opens up more space for prose that can evoke a feeling or style.
I do not think descriptions of powers (spells, abilities, etc) need to be one or the other (prose vs mechanics), but can be both.