All true, but depending on how important it is then putting the following in your CSS will enable most all browsers except for IE to do so without images:

-moz-border-radius: 3px; /*--CSS3 Rounded Corners--*/
-khtml-border-radius: 3px; /*--CSS3 Rounded Corners--*/
-webkit-border-radius: 3px; /*--CSS3 Rounded Corners--*/

Fewer images translates to a faster site, but it's true that many people still use IE. Depends on what you want! :o]