The reason no one knows the hour nor the day except the Father, is that the day is not a set appointed date, it is a day of characteristic. Just like when Jesus came, the characteristics of the day were exact to fulfilling His coming. Even so, the days which we are refering to as the end times are (and have been for some time) been ascribing to the characteristics which are desrcirbed in the prophecies.
To give you a direct answer to your question, I would say we could expect to see another 20 years before the "antichrist", "the son of perdition" is revealed. I, for one, am watching, not for the antichrist, but rather, for those who are already antichrist, to see who they are drawn to.
Everybody has their opinion of how the prophecies are interpreted. Most of everyone agrees with the main stream interpretation; that of there being a one world religion. However, I do not. There is nothing in prophecy that, as far as I can see, describes a one world religion. The mainstream belief is based on there being a "false prophet", and the belief that "the antichrist" will stand in the Holy Place proclaiming himself to be god. This does not necessarily indicate "religion". John said in Revelation, "The testimony of Jesus is the spirit of prophecy." If you read everything about the "false prophet", you will not find anything specific that has been prophecied by this "false prophet". It is "assumed" that the "false prophet" is prophecying about the anitchrist, but I have a different understanding; which I can't go into right now since I am at work and it would take too much time to go into right now.
I have to go back to work.
Jeff