Is Microsoft really serious about WP?

Appears Nokia is more serious about WP (because their lives depends on it, at least for now) than Microsoft, who is currently cool about having no software or hardware parity (not comparing apps here) to other bigger mobile operating systems and want us to wait until at least next year (announcement + carrier review + update push) to receive any meaningful update.

Things literally has stayed same from the perspective of the users since Mango except for the wide tiles and other minor features. When was Mango released again? May 2011? And we're not supposed to expect anything big until early 2014. Makes me wonder whether Microsoft is really serious in the mobile business considering the glacially slow development and improvement.

BTW, what happened to the early access program promised in Build 2012?