reflection on SaaS and tadionational software

If we think a web page is a software, then a web site is a SaaS. Why is Saas better than traditional software? well, if I want to use the software, put the url, then I am ready to rock. No go out buy the software or download the software, no CD installation or download installation, no reboot machine, no risk of virus, no upgrade. However, everybody looks at the same thing; everybody follows the same processes, which is embeded into the web site programming. I can't change how it looks and how it runs.

Then there is the trend of personalization. Web site users can change the skin, change some language preference, font preference, and etc. But I still can't change how the website process runs.

I am waiting for the next change. If Gmail doesn't provide a chinese spell checker, I can always plug in a kingSoft chinese spell checker in my gmail. Is it similar as Salesforce AppExchange? I hope their SalesforceOS is based on stardard web service grid, which indicates the age of Software Plug-n-Play.