Grammar... or the lack thereof

I find it interesting with today's "me first" attitude that use of the word "me" seems to be avoided at all costs, both in written and spoken English. For example, I have a colleague at work who always says "let Joe and I know" or similar, when "let Joe and me know" is proper. If you don't believe that, just delete the "Joe and" part of the phrase and tell me what sounds correct. Also people will even avoid using "I" by replacing it with "myself," as in "Joe and myself would like to meet with the research group at 2 o'clock."

So what is this aversion to plain old "me" or where appropriate, "I"? Is it some kind of misplaced modesty or what?

Then in written form only, everyone and his proverbial brother seems to confuse "lose" with "loose," as in "use it or loose it," or "I'm loosing my mind." Watch for this one in just about any blog or chat room you visit -- I guarantee it will show up without fail.