Re-openning last session in Chrome

Yesterday, I updated my my Chrome browser from version 0.2.149.29 to version 0.2.149.30, I didn't notice much difference and I didn't expected so, because usually this kind of minor updates are just about stability & security issues.
But actually, there was a difference. Usually, when I close my browser, I keep few tabs opened to continue what I'm doing next time. The one problem I was facing earlier that when I open my browser again, the browser has to reload all the pages I left open from the last time. This might not be a problem for people working ADSL or T1 connections, but for me, it is! Because I'm working on a dial-up connection, which is too slow.
But now with this latest version of Chrome the problem has been resolved. Now, even all the old pages are reopened, but they don't reload until I open that tap. So when I open my browser the tab that I was last on will reload, but others won't till I click on it to open it. Or after a while from opening Chrome, other tabs will load one after another, even if I didn't opened that other tabs.
There are some other stuff also under the hood that I don't know yet.