The Japanese version of Demon's Souls is scheduled for release in early February of next year, but it looks it won't be the only one making it out that month. Siliconera suggests that the Asian version will also ship in February and most interestingly will be entirely in English. The site recently went hands-on with a new build at the Asia Game Show in Hong Kong and have discovered that the demo was, in fact, completely in English.
Now, it is possible that the final release in Asia may not be in that language; however, that is really moot. It's most important to note that there is some form of English language version and it is currently in the works. At the moment, there haven't been any mention from either SCEA or SCEE in regards to North American and European releases for Demon's Souls.