I saw the season 6 Episode, 'Let's kill Hitler", I UNDERSTAND SO MUCH MORE NOW! I was always so confused on who River Song was and who Melody was and all that stuff. =P
It cleared up a lot of stuff for me. And now i want to watch more of it!
I got tired of all the billions of dalek and cybermen invasion episodes. The only episodes that I really liked were the ones that weren't on original/alternate universe Earth. Which is why I loved Gridlock a whole lot.