According to Fangoria, The Grudge that we saw was an edited version of what the Japanese will see. This information came from the Ringu/Juon producer Taka Ichise. Apparently he said it will have more "hard stuff" and if this was released here it would warrant a "R" rating.
No word has been released on whether this version will be released on DVD here. We can maybe count on a double dip effort to push the unedited version of the film.
Source: Fangoria