I personally like the new interface of the Mail program found in OS X Lion. But I have to say the program sucks hell. It uses gigantic amounts of memory just for e-mails. And also a heck of a lot of CPU. What the hell is it doing in there to take so much resources? As you can see here, the Mail program is using 2.25GB of RAM and 9.58GB of virtual memory (in the swap folder of the HDD). I have seen it use up to 180% of my cpu (around 90% of each core). This makes the whole mac slow down, freeze, crash. It takes forever to open another program because there is NO RAM left (well 2MB that's useful!). So there you go, it saturates my RAM and uses a lot of hard drive to slow everything down and finally I need to force quit it and start it over because it's so unstable I'm not even able to send an email. So guys please be careful when installing OS X Lion and make backups and a second partition because it is really unstable. And Apple has a lot of work to do on the program before this summer.