Web 2.0 Developer's Worst Nightmare!

Hey man what you are facing ,others have faced it and i would want to believe that you probably used javascript  or so. Well when it comes to web 2.0 you have to build and test in almost all browsers you could lay your hands on. Particularly those that are very popular IE and of course the most beloved Firefox. Gone are the days when you build sites with one browser in mind . Building a true web 2.0 entails  not RAD(Rapid Application Development) it involves careful planning. This planning has to do with determining the client browser before hand and render the appropriate interface that is suitable for that client.It is rather tedious , but the work is finally up and running, you sit back and marvel at the work you have done.For this you would some kind DOM hacking  better known as DOM manipulation using Javascript. But unfortunately, a lot of us done like bringing Javascript in to the picture of web development, too bad, everything has its place and i must tell you if you are ever going to do a  near perfection web 2.0, you would need to learn not how to do it but how to do it better. I have written a number of Javascript related articule that is commonly used in web 2.0 particularly, patterns in Javascript to help in handling issues of this kind. You could check it out on http://www.javascriptrev.blogspot.com , I am still putting out some more on that.
For now welcome to the world of real web programming where everything that glitters is not always gold. 

Browser incompatibility is a horrible menace and it can't be evaded at least while we still have companies like MSFT that will rather prefer to create their own standards and follow others. However, there are safe practices that can be followed to minimize problems arising from browser incompatibilities.

One of them is to use well developed CSS frameworks. I tend to drift towards Blueprint - http://code.google.com/p/blueprintcss/. There are a lot more other CSS frameworks out there that you can use for your apps. Using a CSS framework will save you from having to do a lot of CSS hacks since they have already been incorporated.

Secondly, if you do lots of AJAXy kind of activity in your apps, instead of writing your own XHR routines, you are better of using a mature library for that. Examples include jQuery (my favorite), Dojo, Script.aculo.us and MooTools.

Third, avoid using clever Javascripts. You're better off using the Javascript libraries to do your DOM modifications than doing it yourself.

Fourth, the W3C standards are great. Ensure your HTML/XHTML are well-formed and pass the syntax checks and so on.