Blu-ray has more or less won the format wars for the current level of HD (1080p). Although no one is ever completely certain where the formats will go in the future, the likelihood is that there will not be a replacement format of optical disk in widespread distribution. Future distributions are likely to be done through purely digital mediums, such as streaming and cloud storage. From that standpoint, Blu-ray is probably an acceptable risk. (Even if there were to be a later update, given the slow adoption of Blu-ray, it will likely be some time before a replacement is warranted.)