I just wanted to drop in one more time to say thanks to all of you true believers!
Although I am still concerned about the lack of Mac support - and still not convinced I will ever grow to love the buttons on the side, I have decided to put aside my misgivings, take the proverbial plunge and go ahead and get the Sony 505. So thanks again for the advice and counsel - and now it's time to celebrate!
BTW, One of the key factors influencing my decision is that the 505 is now available at Costco (not all locations, just a select few - you can get the details at Costco.com) - which means I can take it back if I don't like it and they will not give me a hard time about it (I love Costco!).
(the only bad thing about it is that Costco apparently does not have it in blue -

)
Having burned hours reading and chatting and studying and reading more and chatting more and studying more, its time for the hands-on phase of the research - I will be checking back in to let you all know how it is going (and to pose many more newbie questions, of course).
-- Rique