Don't really know about the overseas markets, but here in the US, Apple just announced this morning a bump in the iBook speed and a drop in the price. The cheapest one can be had for under us$1000! I really don't know where to start for finding someone who will export them to India or elsewhere, though. I guess you could start here:
http://dir.yahoo.com/Business_and_Economy/Shopping_and_Services/Computers/Retailers/Macintosh/
The screen size of the iBook hasn't changed, so my concern there still remains, but there's no way I can say what will work for each of you, only what works for me and for people I know. You each have to weigh CPU, monitor, disk, size, weight, etc... and make the call for yourselves. Even if 99 people said iBook and one said PowerBook, the PowerBook might still be right for you. If majority ruled, there would be only one computer - a cheap Dell running Windows 95/98 (yes, still the most installed OS in the world) on a 17" CRT with no DVD drive.
The fact that there are so many opinions on what's better, what's important, etc... should demonstrate that everyone needs something different. All I can do (and all I have done) is tell you what are the differences between iBooks and PowerBooks and what works better for me. I'm not sure there's anything else I have to add to this thread, although I will check back occasionally.
Best luck making your decisions, and I hope that my information has been helpful!