As comic head and a fan of Snipe's movies, I don't think Blade had anything to do with the current success Marvel has with it's movies.
Blade was a successful series, but prior to Blade, Marvel had always planned on X men and Spiderman movies going back as far as the early 90s.
I remember reading about it back then. In otherwords, X men and Spiderman movies were going to happen regardless of whether Blade was a success or not, and like it or not, SPM and XM were the cornerstone of the comic franchise. I think X Men and the OG Spiderman is what really jump started this. Add to that, I don't think most people even know that Blade was a Marvel character to even give it that credit.