With Black and White featuring no old Pokemon Pre-National, Gamefreak decided to bring them back in spirit with similar 5th gen counterparts to fill their roles. Which Pokemon lines do you see as being these "replacement" Pokemon?

Geodude/Graveler/Golem -> Dangoro/Gantoru/Gigaiasu
Zubat/Golbat -> Koromori/Kokoromori
Koffing/Weezing or Grimer/Muk -> Yabakuron/Dasutodasu
Weedle/Kakuna/Beedrill -> Futsude/Hoiiga/Pendoraa
Caterpie/Metapod/Butterfree -> Kurumiru/Kurumayu/Hahakurimo
Machop/Machoke/Machamp -> Dokkora/Dotekkotsu/Roopushin
Hitmonlee and Hitmonchan -> Nageki and Dageki

I think Pikachu was replaced by Chillarmy, Pidgy with Mamepato, Fearow with Wooguru, and Magnemite with Giaru (Gear).

Pikachu -> Emonga
Meowth -> Choroneko
Poliwag -> Otamaru
Tentacool -> Pururiru

Nobody else sees Buffaron and Tauros?

I have no idea what any of these comparisons are without a picture. @_@

That little ice cub/bear = Teddiursa and Ursaring?

No. Nonononononono. Emonga is a perfect example of Parchurisu. Mamanbou, Luvdisc. Baffuron, Tauros. Those are all the ones that were though to evolve, but didn't.

Chansey = Tabunne (No need to explain)
Roselia = Doreida (I see a lot of resemblance)
Voltorb = Tamagetake (Both are based off a Pokéball)

Those are the ones which I think of besides what has been posted over here.

Churine reminds me of Oddish while Churine's evolution, Doredia, reminds me of Bellossom. Look at the "skirt" and pink flower. It's also shaped sort of like Roselia. So someone took Roselia and put a freaky Bellossom costume on it.

Arcanine -> Urugamoth.

Both are high-BST fire-type Pokemon considered "legendary" but not officially legendary or pseudo-legendary.

Mewtwo -> Genosect

Both are legendaries that were modified by the games' resident criminal organization.

Drowzee -> Munna (I can't believe nobody said this one yet.)

Magikarp/Goldeen/Finneon -> Basurao

Grimer -> Yabakuron

You always need the region fish and bird. It's not really "replacing" the old one.

Anyone else noticed Gochiruzeru is replacing Gardevoir?

And Zoroark would obviously be replacing Lucario. Being a diehard Lucario fan, I personally think there should be a scene where Lucario pwns Zoroark with Aura Storm for replacing it. Just think, with the enhanced graphics in B/W, it'd look exactly like in Brawl, but even bigger, and maybe there should be a huge explosion in the end that creates a huge crater afterward. The whole screen would just be a blue beam of epicness. And-*Goes on huge lecture*