The basic fact of the matter is we will (or should) lose plenty of good players from ODIs after WC2007...
Gilchrist, McGrath, Martyn, Hayden if he makes it back to the squad, Gillespie if he makes it back to the squad, Ganguly if he makes it back to the squad, Dravid, Tendulkar, Astle, Fleming, Harris (there really is genuine hope that he might make it back to the squad), Bond, Inzamam-Ul-Haq, Mohammad Yousuf, Shoaib Akhtar, Gibbs, Pollock, Jayasuriya, Murali, Atapattu, Vaas, Lara, Chanderpaul and Dillon if he gets back into the squad.
Whereas after WC2003 the losses were smaller: Knight, Caddick, Stewart, Hussain, Srinath, Saeed Anwar, Wasim Akram, Waqar Younis, Donald, Rhodes, Kirsten, Tillikeratne, de Silva, Hooper, Campbell, Andy Flower, Guy Whittall. Though there were players who we've lost in the meantime... Bevan, Lehmann, Grant Flower, Jacobs, Klusener, Cairns, and with hindsight it'd have been much better for their teams if they'd retired after the Cup. Although Bevan's being dropped was stupid.
But yeah... WC2007 should be a watershed, and obviously there'll always be World Cups in the future where loads of good players retire simualtaneously. Or certainly there should be.