Sep 07, 2011 08:53 AM|ankur.nigam|LINK
You need to understand, HTML5 has got to do nothing with server controls, its a standard which needs to be satisfied by browsers vendors.
The approach that you are taking looks fine to me.
If you view the page created this version of control on browser that supports HTML 5, I dunn think there should be any issues (before you test the ASPX pages using these controls, just create an HTML page with HTML 5 markup and check if it works.)
If you have any further doubts, let me know.