King_Pietersen suggested that India would have West Indies-esque decline. I think that's impossible just due to the sheer volume of cricket played in India. We obviously won't have overnight replacements to the likes of Tendulkar, Dravid and Laxman, but that doesn't mean that we won't eventually have them. In the 90's, our batting consisted of basically Tendulkar and a bunch of guys who were very unpredictable and not very confidence-inspiring. A select few eventually developed into some pretty good cricketers. As fans, I think we always give budding cricketers too short a leash. As Indian fans, even more so. The best players playing the game right now weren't awesome from the get go. A lot of them dabbled in failure at the beginning of the career and eventually developed into really good players. You don't come into international cricket as a finished product.
Secondly, if you compare our Test team today to our team in the previous generation, you would have to be incredibly shortsighted to not be able to see the progress we have made. We've still kept our home a fortress--although it's not as strong as teams around the world have grown accustomed to playing spin. At the same time, we've improved in our away record tremendously. We may not be winning series' all over the place, but we're drawing and winning a lot of Test matches. In the previous generations of Indian cricket, when we were touring the likes of Australia and South Africa, a draw was considered as good as a win, and a cause for celebration. Now, when we draw a match, it is considered a lost opportunity for a win.
Finally, the volume of cricket has gone up so much, especially Twenty20 cricket, that I think we are losing focus of what really makes a good Test/ODI team. Twenty20 is far too tied with luck for it to be an accurate basis to determine how good a team is. For example, the way the Bangladeshis bowled in that last session against England and batted in the session immediately after, they would have won a Twenty20 match against England (of course, this is a hypothetical suggestion; purely a theoretical device). England, the better team, strung together more good sessions than Bangladesh which is why they are in the ascendancy.
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I don't think you will see a max exodus of the Indian batting line-up. I believe Laxman/Dravid will ease out first, followed by Tendulkar, in a couple more seasons. As Tendulkar has already shown in the ODI line-up, a mixture of experienced and young cricketers is a potent combination. We'll be looking to do the same with our Test lineup, hopefully.