I suppose if we figure out how to make click-to-pay work for both the "I'm using an online wallet service" and the "I'm using the client" cases, then users won't have to know how to copy&paste addresses and human-type-able addresses won't be critical.
Maybe a little bit off-topic, but I think better usability is essential to bitcoin's success.
Highly recommend this book:
http://www.amazon.com/Change-Function-Technologies-Others-Crash/dp/B000NA6U2O/ref=sr_1_1Book description:
"After years of studying countless winners and losers, Coburn has come up with a simple idea that explains why some technologies become huge hits (iPods, DVD players, Netflix), but others never reach more than a tiny audience (Segways, video phones, tablet PCs). He says that people are only willing to change when the pain of their current situation outweighs the perceived pain of trying something new."
"In other words, technology demands a change in habits, and thats the leading cause of failure for countless cool inventions. Too many tech companies believe in "build it and they will come" build something better and people will beat a path to your door. But, as Coburn shows, most potential users are afraid of new technologies, and they need a really great reason to change."