The period in which you can reserve train tickets has been increased from 90 days to 120 days. Apparently this is being done on an experimental basis. This does not affect some short distance trains like Taj Express and Gomti Express.
Reactions to this change have been on mostly predictable lines. Most users have gone through a lot of wasted time and effort in booking a ticket via IRCTC and it shows. Most of the comments were along the lines of "Railway tickets can now be booked 120-days in advance. That is 30-extra days for IRCTC website to die on you". All justifiable :D