web 2.0 and AJAX

I think two of the most latest developments in the software sector especially internet based is web 2.0 and AJAX..
Web 2.0 is definetly the future.. it has a lot of potential and is growing ... Many websites have already shifted to web 2.0.. it makes the website more effecient and interactive... One of the best features of web 2.0 is it allows you to run softwares on a web browser.. thats how the concept of WebOS was born...Web 2.0 is also being brought about in blogs,news,wikis,RSS etc..
AJAX is a type of programming hugely appreciated and used by GOOGLE..the gmail chat window you find in your gmail inbox page is an example off AJAX.. it has great potential and many web developers are using it.. It makes your webpage more interactive and also more quicker.. as if any value has to be updated the whole webpage need not refresh ,only that part of the webpage would refresh.. saving a lot of time and bandwidth..AJAX which is based on javascript and xml is widely used and will soon replace many other old programming techniques...