I would still be upset about a two years lag, especially since I am rather positive that such features existed far earlier than 2006 in other clients and even if that wasn’t the case, it shouldn’t take Google Mail (Google!) two years to implement such a trivial feature when it is already available in a small open source project.
This feature was a Gmail labs feature for quite some time before being fully implemented in March of 2010. This feature is old news (though not as old as claw mail), but I can understand why people just discovering it would be excited about it.
Exactly! Just discovered this feature - pleasantly surprising.