I have my TP OCd to 1.5GHz. Fresh Boot .. memory usage is ~380MB. Within 2 hours of use (opening / closing apps) ... the memory usage is ~670MB ... with no apps running.
The other day I tried to open Adobe PDF reader and the OS said (paraphrasing) 'to close open cards' ... except I had no other cards open. That triggered this whole 'memory monitoring' project.
Definitely appears to be a significant memory leak ... since we are talking memory usage bloat within a matter of hours.