No it did not. Contrary to popular beliefs, I feel like this game was the least different from the last one, in such it did not introduce something new that is a major factor to how the game is played compared to the other gens. Gen 2 introduced new types and balanced the whole typing, it's very different from Gen 1. Gen 3 introduced EVs, IVs and natures, and thus the games are vastly different from the last. Gen IV introduced the physical/special split which is actually a very big change.
But what has B/W introduced? Dream World and third abilities? That's not too big. Triple Battle and Rotation? ...nah. It's just gen IV on crack with weather.
Of course the whole thing is arguably different to a (I hate this word) "casual"'s point of view. But to a lot, it narrows down to the game's design. I felt B/W, as a whole, had terrible decisions in its design. Unova is a boring region, that feels completely empty, dull and especially short. (There are exceptions of course but it doesn't change anything.) The region design just isn't as memorable and limited to explore. B/W are the only games in which I completely put down and haven't turned back on (sold it actually) because of the very lackluster post-game.
I also don't see the praise in its story, this whole dark theme didn't do it justice, especially not in a main Pokemon theme that follows the past game's simplicity and audience. Pokemon Colosseum/XD did it right with shadow Pokemon, loveable characters and overall visuals. (However, it was targeted at an older audience. But B/W wasn't.)
The characters are also boring and uninspired for the most part in terms of design and characteristics. It's not like the main games had a lot of interesting and lovable characters, but I feel B/W as a whole was a step down in that department, especially with the new evil team and ugh N. (Luckily B/W2 fixes that with the new gym leaders and especially Corless.)
One thing it did right in the designs is the new Pokemon. I complained about the design of the game, but actually praised the Pokemon? Oh god!
In all seriousness however, the new Pokemon was definitely a step up from gen 4, as the designs were superb and inspired, even if their overall abilities gameplay-wise is vey questionable. (The new Pokemon really ruined the metagame for a lot of people.) HOWEVER, there is a huge problem in those new Pokemon in that they're the only ones available throughout the whole main game. That is just a poor decision, as it loses the overall variety in making your teams and it just feels limited. A lot of people would love using the old Pokemon should they dislike the new ones. (I don't support nostalgia-glass and those people, but you have to give them a bone if you want them to bite.) If this is their idea of a reboot, then it's just a poor attempt.
Fortunately, again, B/W2 fixes most of these. However, with the bad taste that B/W left to me, I'm not sure I am really interested in it.
Another thing is that what makes it deserve the higher score from other, arguably better, Pokemon games? Simplicity is a HUGE factor, as mentioned here, because a huge amount of people just pick-up the game and beat it fast, without spending too much time with raising their Pokemon and doing the post-game aspects. This is also huge for kids because it's not too complex for them. (D/P/Pt...)
Of course this is purely my opinion, and are not factual points whatsoever. I just feel B/W changed what shouldn't have been changed and kept what shouldn't have been kept from the main Pokemon games.
Overall, I would say that BW really deserves the 40/40. It's graphics are definitely nothing if you compare them to RPG games on other consoles, like Final Fantasy on the PS3 or something like that. But for a DS game, it's hard to find anything better than BW.
Graphically, it looks horrible. If you want a DS game with better art styles and visuals then Hotel Dusk, Warioware, Okamiden, Ghost Trick, Yoshi's Island DS, Rhythm Heaven and Metroid Prime: Hunters are just a few examples of better games visually and graphically (and generally...well, imo :P). If you want RPGs exclusively, Final Fantasy 4 DS and The World Ends With You are the first to come to mind.
They should have kept with HG/SS's style, but maybe it'd make B/W look too similar.