In my estimation, Marvel's policy of not marrying cover to interior story content hasn't particularly produced some shoddy cover work. In fact, I think they have managed to update their style to finally move it away from the stereotypical, copy-laden, story-focused, generic covers that have plagued the industry for decades. I did a quick grab of a 1970's cover by one of the most popular comic artists from the era from my favorite online auction house. I took the first super hero cover I found, and it happened to be a Neal Adams cover from a very popular title. It happened to be at least minimally story-focused.
I don't think this cover has a huge advantage over any of the covers I grabbed from Comic Book Resources latest posting of Marvel solicitation copy and covers.
If anything, I think that the two new covers are at least as eye-catching, at that seems to be the most important feature of any cover.
This all may be purely editorial or management directed, but when they choose to, editors and artists can also come up with some great modern covers that function as storytelling.
Much maligned Mike Mayhew, for example, produced this cover for an upcoming issue of The Pulse, and I think it does a great job as a story tease, and as an eye-catching cover for a super hero title. It tells you enough about the interior story, and has a strong enough design sense to direct your attention to it on the stands. I only hate to imagine what adding all the required cover copy will do to these images.
And lest I forget, Marvel can also provide some awful cover fodder. This new title was the focus of their latest in-house preview magazine and it is outright ugly. I only hope, for the title's sake, that this cover is not the final one used.