Just Netflixed this and watched it. It pretty much ended up how I feared it would...something more concerned with being as literal a translation of the comic as possible, rather than being as good of an animated feature as it could be. Like it was a celebration of the comic first, a film/feature second, which is pretty much a bad thing for any film/feature, regardless of what it's based on.
To begin with...I think there's two ways to look at this piece, and neither are really that good. I actually feel that Superman Returns, in its own way, suffers from the same symptoms. As mentioned, for someone who is familiar with the source, there's a feeling of redundancy...we've seen this part note-for-note, and it was better in the original anyway...better suited to the comic page and a certain vibe that comes across that way. It's actually the parts that weren't literally from the page that stood out as good and refreshing.
From the other side of things, if you're not familiar with the comic...what you get is something that's rather dry and feels like it's just skipping over some things at points. It's there, but it doesn't really move you or carry you along very well. You're watching it, but not really experiencing it, if you will. So basing it so closely to the comic pretty-much worsens it for both sides.
Also....although there was some nice design and artwork elements in addition to maintaining the character style of the comic...it still didn't help it as a feature, and with every DC (or even Western) 2D-animated release, it's more and more evident how much more developed and sophisticated Japanese anime is than our stuff, even in the smaller-scale regular shows. Obviously, their industry puts more into it than ours, but hell...we should be taking it that serously over here if we want it to be as good as it can be.
It's not as if the more complex and sophisticated the animation, the more it's evident that they couldn't do live-action. Not at all...it actually highlights 2D animation as an art form more and accents things that basically can't be done live-action, or at least not have the same creative feel. Western animation actually does remind you that they're on a budget, and just not as good as other parts of the world. People high on the totem pole just don't care enough, and only really see it like lollipops....make it cheap and fast so the kids will want it.
Okay, that's not what Year One completely is, but that's a big part of what it's limited by animation-wise. But even aside from that, I think they should have treated it more as an adaptation for an animated motion picture...instead of the video equivalent of books-on-tape. Heck, some people may actually like that as an approach, but it really could have been so much more.