Just in case any of you were wondering. This isn't the arcade version, nor any kind of remake. It's a port of the Dreamcast version. Take that as you will, but a lot of Dreamcast fans should be pleased as punch.

XBLA Soul Calibur Is The Dreamcast One, Not The Arcade One

Soul Calibur's coming to Xbox Live Arcade. Hurray! But...wait. Which version is it? The magnificent Dreamcast version? Or the, uh, less magnificent arcade version? Rest easy, kids. Namco Bandai have told Shacknews that "the game is based on the Dreamcast version with no major additions or subtractions". Glad that's sorted. Now all we need to know is how far over the 150MB limit this thing's going to come in at, and we'll be all done.
Soul Calibur XBLA Based on Dreamcast Version [Shacknews]

Well that should be good news then, right? It sounds like the DC version was better than the arcade version. From one person in the comments section:

"Anyway, I worked in a Babbage's in a mall when the Dreamcast launched. I had never heard of the game but I saw tons of it when the demo units came in, bought it and a Dreamcast, etc.

Then one day the dink-ass arcade we had in that mall got an arcade version. Man, I had always heard the Dreamcast version was better but I didn't know by how much until then. The Wikipedia article doesn't mention what exact hardware the arcade version ran on but I seem to recall hearing it was PlayStation 1 hardware essentially. It would make sense. If nothing else the resolution on it was pretty low."

I don't really remember how the arcade one was since it was such a long time ago, but I thought the DC one was pretty damn good :) Sounds like good stuff:D

 the arcade was on the system 12, which is basically a souped up playsatation, i.e. more ram, faster processor ecetera 

regardless the dreamcast release is much much prettier 

Well, it's the dreamcast versions' graphics plus some