Continuing sn_22's excellent idea:
Hit of the year: The X Factor. Sorry if this is predictable but in my book the highest rated show of the year is the hit of the year, end of story. To actually manage growth from 2009's exceptional ratings was brilliant. Strictly Come Dancing, EastEnders, The Inbetweeners and Downton Abbey also deserve a mention here
Flop of the year: The Prisoner. No contest. Losing 90% of its BGT lead-in was shocking and then that 0.7m for the last episode!

Modern Masters, High Street Dreams, Amanda Holden's Fantasy Lives, Michael Winner's Dining Stars, Seven Days, The Morgana Show, Material Girl and Marco's Kitchen Burnout all also should be mentioned here (I've probably missed a few too).
New hit of the year: Downton Abbey. X Factor lead-in or not those ratings were stunning for a new drama. Sherlock also deserves a mention here.
Jaw-dropping rating of the year: EastEnders Live. Came totally out of the blue and nobody expected it. The Inbetweeners also deserves a mention here.
Mystifying rating of the year: Countryfile. It's not a bad show, but 8 million viewers?!

Total Wipeout getting 8m at the start of the year and Wild at Heart also deserve a mention here, the former for similar reasons as Countryfile and the latter because it's utter rubbish and yet is one of the biggest dramas on TV!
“So glad that flopped” of the year: High Street Dreams. Lazy, lazy, lazy programming, and typical Jay Hunt fare. Amanda Holden's Fantasy Lives, Don't Stop Believing, Seven Days and primetime Dickinson's Real Deal also deserve a mention here.
“Such a shame that flopped” of the year: Married Single Other. It had a weak first episode but I grew to love it in the end, so a shame it didn't do well. Luther also deserves a mention here, as whilst it's returning it's only for specials and the ratings weren't great, which again is a shame as I really liked it by the end of the run. I also want to mention Frankie Boyle's Tramadol Nights here but I doubt many will agree with me.
Best Channel: BBC3. Most of their programmes really aren't my thing but they've managed to homegrow a lot of new hits this year and have come on leaps and bounds under Danny Cohen, who hopefully can do the same with BBC1. E4, ITV3 and ITV4 also deserve a mention here.
Worst Channel: C4. Dreadful scheduling and lazy commissioning have meant that this has been a very poor year for C4, with old hits floundering (Secret Millionaire, How To Look Good Naked) and new shows flopping (Ramsay's Best Restaurant, Seven Days, Wedding House), meaning that they have very little to keep them afloat, and poor scheduling has harmed shows like Come Dine With Me, Frankie Boyle's Tramadol Nights and The Million Pound Drop.
They need to shape up fast or things could really turn sour. I see a number of high profile shows begin this month, such as Ten O'Clock Live, Famous and Fearless and new Mary Portas and Gok Wan shows, which they'll be hoping do well. They'll also need the fish season to perform well. I notice Gordon Ramsay has a programme about sharks airing this month, and it sounds better than the dire Best Restaurant format, so it'll be interesting to see if he still has some ratings life left in him
More4 and ITV2 deserve a mention here.
Looking ahead to 2011: The New Year certainly will be interesting, as BBC1 have decided to swap their 9pm dramas around so Silent Witness gets better slots but Hustle gets demoted to Fridays. As Hustle skews young I don't think this is a wise move but I hope it holds up well. Silent Witness should do well as ever. The Magicians should start well tonight but the reaction has been largely negative so it'll be interesting to see where it ends up. I hope Zen does well as it looks great. I think it'll get 6m+ tomorrow.
ITV1 have made some interesting moves at 9pm, and I'm glad they've decided to address Tuesdays as Taggart should get 4m or so there which would be a decent improvement for them there. As it's a co-production they'll only be paying £300k per episode so it's not like they're wasting a really expensive drama there. Kidnap and Ransom looks great and should do well on Thursdays, which I see ITV want to focus on a bit after the disaster of The Bill. Comedy Rocks should do OK on Fridays and Wednesdays will be fine, but The Biggest Loser on Mondays could go either way. They seem to be taking a 'change your life for the better' approach with the trailers which may help it, and ITV really need a midweek factual entertainment format and they clearly have faith in this, but I think it could get anything from 2m to 6m and I'll be very interesting to see where it ends up. Primeval and Take Me Out should do OK on Saturdays (Primeval will be interesting though), but Sundays could see Dancing on Ice step up like the other talent shows or really get left behind. Based on what we've seen so far I think the latter is more likely unfortunately but i can't see it falling too much from last year.