I just read a great article by Dave Ward on Encosia.com about the disadvantages of using ASP.NET UpdatePanels. The article describes how using an UpdatePanel to get the current date from a Web Method used 872 bytes of POST communication vs. a JSON version which used a mere 24 bytes. Not only is 24 bytes better than 872 because of bandwidth and communication time, but also processing time once it’s received at the client. Great article.
There’s also a great discussion in the Comments section of the article.
Thanks Dave for this great explanation.