Apparently according to cricinfo, the following are the tours till 2011. (Tests only)
WI hosting SA in May to June.
Eng hosting Pak vs Aus in July
Sl hosting New Zealand in July.
The Ashes in Aus, winter.
Which means, after Aug, none of India, Sri lanka, New Zealand, West Indies, South Africa have any tours planned till World Cup in Feb 11 which leaves a yawning gap of over 6 months in these countries' calendar. Further, Pakistan too don't have any tests after their series against Aus.
I find it quite inexplicable, and am inclined to blame cricINFO for not having updated their database. I always thought India were touring Sri LANKA and South Africa this year.
Pl feel free to correct me.