Not so long ago (March, 2009), Gartner predicted that the worldwide hosted virtual desktop market would surpass $65 Billion by 2013. I'm not sure where we stand today, but VMware seems cautious about making any predictions on mainstream VDI adoption. Alessandro Perilli reports on virtualization.info that VMware recently reported their 2010 Q1 earnings and had a Q&A session at the end of the call. VMware stated:
"Exactly when this market is going to tip though we don't know. We were saying - engaged and focused on it, but I couldn't tell you if its going to be at the end of the year or next year or exactly when that's going to be but our eyes are certainly on the ball and we are going to make sure that when it does tip, we are there to take advantage of it."
This may just be my opinion, but I agree with VMware here. I personally haven't seen the adoption that everyone predicted. I think we'll get there, but I'd be hesitant to predict a date as well.