In the previous releases we've had the following icons for Detail Levels: Coarse, Medium and Fine.
With 2010 we now have these.
While I appreciate the more accurate portrayal I do find it "harder" to determine at a glance which detail level is used now. Since they all have the "same" kind of pattern I now have to actually stare at the icon longer. Perhaps it is just my aging eyes but with the previous empty white square it was easy to just glance and see that Coarse detail level was in use or not. It is still harder (for me) to determine whether medium or fine were being used with the older version too but then not a lot of views use Fine by comparison.
Remember that the Detail Level settings are also available in the View Properties dialog. I haven't used that route since the View Control Bar was added though. Well I have altered the setting in the dialog but only because I already happened to be there doing something else.