India's main worry is their fielding and bowling which is sub-standard and is hurting them right through the season. Although India won most of its matches this season but they won because of batting and where batting didn't click they lost, take example of Final in Dhaka against Sri Lanka where India wasn't able to score close to 300 and they lost. So I feel its time to look at some fresh options in bowling and India have options in their reserves. India also have to work hard on the inability of not picking up the tailenders cheaply because this is hurting them badly since last 2 seasons in all forms of the game.
Moreover India's worry increases because of the injury to Sehwag and he looks like doubtful starter for tomorrow's game. India have already lost 4 key players. Also this season MS Dhoni remained unlucky as far as toss is concerned, he lost most of the tosses.
As far as Proteas are concerned Kallis looks in great form with bat and ball. Moreover their fielding is great.I feel tomorrow they will play Amla instead of Loots Bosman because Amla provides solidity to the batting order. I think they lost first ODI because none of their batters stayed at wicket. I feel Proteas will win tomorrow as India given them advantage in 1st ODI by allowing their lower order batters to take the match till last bowl. So I feel its advantage Proteas for 2nd ODI.