Bleeding Cool has a partial advance listing of Marvel's solicitations for May (it doesn't include the trade releases). By my count, Marvel has 86 individual comics in their solicitations. Of those 86, twenty-three titles are being double-shipped (so 46 comics) and one comic is shipping weekly (5 issues in total). So overall, 51 of the 86 are comics they doubling up (or more). So in essence, there are only 62 actual unique titles Marvel is producing in May, and the rest are made of double-dips into their reader's wallets.
My first question --- how long can they maintain the quality on books they are double shipping? Most writers can handle more than one book a month. But they definitely lose consistency with the artistic teams. In order to double ship books like this, they will absolutely have to rotate artistic teams more often. I find that to be kind of a drag, especially if a big part of the draw (no pun intended) on a particular book for a reader happens to be the art (team).
But this also begs the question --- is this really what readers want? I know it usually seems like more of what you like is better, but if you are a reader who happens to be following most of those 23 books they are double-shipping, now you're finding yourself needing to purchase 46 comics instead of just 23. And since a fair number of those 23 titles are the ones Marvel charges $3.99 for, they are really hitting their fans extra hard in the wallet. This doesn't seem anything at all like a fan-friendly practice. I see it as nothing more than a cash grab --- intended to milk as much money out of their core books as humanly possible. They know they are not getting the same returns on the non-core titles, so they are expecting their hardcore fans to make up for the deteriorating bottom line by getting them to buy more of their higher priced books. Of course, this does nothing to actually grow out their audience, but that doesn't appear to be something that concerns the people who are only looking out for the bottom line.