Usually, downloadable games on Xbox Live can only offer 200 Gamer Points' worth of Achievements. The HD reissues of Resident Evil 4 and Resident Evil: Code Veronica, however, will offer 1,000 Points each, boasting full-fledged Achievements.
This is because they are skipping both retail and Xbox Live Arcade in the West, releasing instead via Xbox Live's "Games on Demand" service. Since full-fledged retail games appear on this service, the two Resi remasters aren't bound by XBLA restrictions.
Despite the presence of retail copies in Japan, the Resident Evil HD remasters are exclusively digital in Europe and North America. They'll be coming to Xbox Live and the PlayStation Network a little later this year.