I'm with Richard in that you can't predict 20 years off....but.
In the next few years, Aus will fall back to the 'pack' ( mostly due to the retirement of McGrath and Warne ). They will remain strong however due to the good system they have in place.
Zim and Bang will continue to fail, but wont be dropped for ICC political reasons.
Technology to 'help' the umpires will take a bigger and bigger part of the game.
Test matches will get more and more draws as daily over rates drop ( due to all the replays needed to check the umpires ). ODIs will drop to 45 overs/side.
Umpiring standards will drop as fewer people go into umpiring because of the abuse they'll get at stanards below those which provide replays. ( the logic will go..test umpires wont give an LBW without checking the replay, therefore there is doubt, therefore the batsman should get the benefit of the doubt and thus, no LBWs should be given. )
Bowling actions will get worse and worse, and whenever any of them look the break the rules, the rules will be loosened.
The ICC 10 year test plan will fall apart as some countries find it 'impossible' to schedule a tour of Zim, and less frequently, Bang. Of course, these countries will still find time to play more popular countries on a regular basis.
A team will bat first against Zim/Ban and bat for 5 days. Zim/Ban will claim this as a success, because they didn't loose.
ICC will fall apart...Countries will revert to the pre-ICC days of each country administering itself, and touring teams having to adapt to the rules used in the host country. Rules ( or at least their interpretations ), will start varying more and more. Tours will be arranged on an 'ad-hoc' basis, and 'test status' will be meaningless...You will be test status if other countries are willing to play tests against you.