I never saw the Invoker as a Divine Sorcerer, I've always seen them as a Divine Wizard that ate the 3e Truenamer.
Yeah, WotC made that pretty explicit -- the Invoker has the "Controller" role, and can take multi-target At-Will powers at Level 1: Astral Wind (blast 3), Grasping Shards (burst 1 in 10), Hand of Radiance (target 1 - 3 beings), Vanguard's Lightning (burst 1 in 10), and Visions of Blood (blast 3).
I wasn't speaking from a mechanical point of view... I was talking more about the fluff of the class. The Invoker was describe as being infused with the power of the god and being able to release that power, rather than praying for, receiving and then channeling the god's power like the Cleric did.
That's why I said the Invoker was like the Favored Soul or "Divine Sorcerer"... because of the 4 divine classes in 4E... the Invoker was the one described that had the essence of the god within him. The others all acquired the god's power through other means.