The Marvel name will help with the marketing of the movie for sure. It will make people curious. It is by no means equal or even close to the Disney or Pixar brand, but it does have some recognition among non comic book nerds.
The success or lack of will be mostly due to the quality of the movie itself.
Both Thor and Captain America opened at 65 millions for their first movies with better name recognition.
I expect this to easily do 50millions, probably closer to 60-70 if it's good and marketed properly.
John Carter made 30millions for it's opening weekend and was marketed horribly, and was a pretty average film at best.
One thing to remember for marvel, they are building a universe...they'll be satisfied with more modest numbers if the reviews are good, and it allows them to expand their cinematic universe by introducing the "space/aliens" aspect of their comic universe into the cinematic universe.
Opens up the possibility of stuff like Captain Marvel, Warlock, Nova, Thanos etc...
I hope the movie is good as a fan of comic books, but also as a fan of sci-fi in general since I don't think we've had a lot of good space sci-fi in a while, it would be nice to have another space sci-fi franchise.