MG Siegler over at Venturebeat explains that:

"This ambitious goal will rely not only on Blu-ray’s new Hollywood studio partners (those who were formerly with HD DVD), but also the growing success of the Playstation 3 video game system, which contains a Blu-ray player. Recent reports indicate the PS3 will outsell the rival Xbox 360 game system this year."

But he advises caution:

"However, if they think it will be such an easy transition from one dominant format to another, they have another thing coming. Many consumers are perfectly content with their standard DVDs, which cost less and does no require an expensive new piece of hardware to play."

This is a prediction that Blue-Ray will NOT acheive 50% share in the global market for movie disc sales by the end of the year.

Obviously we are beholden to Sony's internal numbers in a certain respect, so this will be a difficult prediction to judge. Our process will be to first use any and all respectable industry resources and research tools to ascertain the numbers, and we will require 2 credible sources in order to make a decision (even if one is Sony itself). If two requisite sources are not available, and Sony does not itself make any announcement one way or the other regarding the 50% goal by 30 days after the close of this prediction (i.e. January 31, 2009), we will be forced to make a favorable judgement concluding that Sony did not in fact acheive its goal.