Thank you for your response. Sometimes I've checked contacts when they are "offline" and sometimes while they are "online". I have read a couple of your other responses on this subject, but am still a little unclear. When you said, "last seen' means the last time that your contact was seen online BY THIS SIGNED-IN CLIENT (the contact could easily have been online while this client was not even running, and it would be impossible for this client to know)"
'last activity' means the last time there was some kind of Skype activity (like a call or an exchange of chat messages) between your contact and THIS client (not this Skype name)
I am assuming by THIS SIGNED IN CLIENT you mean me on my own computer which Nobody else uses. If this is the case, there have been two recent times when I have been online and other contacts of mine have been online simultaneously; however, when I scroll over their icons (while online or not) it still gives the same dates and times from several months ago.
Thank you so much
if a contact is online when you check, you will not see any 'last seen' indication, because they are online NOW -- what is reported as 'last activity' will be the same regardless of whether the contact is online now or not
if you think you have seen something else, then I would have to say it is a bug, and should be reported as such (logs from both sides would be required by Skype to troubleshoot) -- but is it really worth it?? -- Skype won't even look unless the issue can be reproduced by using the current public version