Firstly, I missed a couple of stray ampersands in my 'Asides' column. I'm usually quite picky with invalid URLs, but was so excited to hear that Prince William was single again (yeah right), I forgot to modify the URL accordingly. Heh.
I cried out for help - where else but on Twitter... and help came in the form of Dominik Schwind who kindly pointed me to another website which had exactly what I was looking for. Although it was entirely in German, thank God that HTML, like LOVE, is a universal language. So I was able to modify my own parameters - which this dude cleverly separated out - and voila! No more validation errors!
Thanks a lot guys... solved this within 45 minutes ;-) Geek power rules.