Tax

I would like to ask my seniors that what will be difference between Income Tax ammended every year?

I mean that for May 2011 IPCC examination Finance Act 2010 i.e. A Y 2011-12 will be applicable but book of  A Y 2011-12 will be in the market by nov or dec. Till then if i study from A Y 2010-11 ka book ......what will be different other than Tax slab .....

Or should i start studying tax now or after the new book comes?