Q8200 is cheaper, I give you that, but lack of cache, lack of VT, lack of deeper power states... the Q9550 (now only E0 should be on the market) is a far better choice, and it overclocks very well (3.4GHz without any effort at all, 1600 FSB + 800+ DDR2).
Even so, you must have a dud, since Q8200 should overclock much more then what was achieved for the purpose of the article.
E5200 is indeed the "new Celeron". A very good cheap chip, if you get it to at least 3.33GHz (1066 FSB + 1066 DDR2). I totally agree with this choice.
But why did you go with DDR3? It's double the price of DDR2. In real life, if I have to choose between screaming-fast DDR3, or double the amount of that in DDR2... my personal preference is more RAM, even if slower RAM.
So Q9550 + DDR2 could make the list, at least price-wise. With a little OC, it would be the king of this... let's call it roundup. Some may argue that the 955BE is, but I have my favorites.