With my glass half empty view on life, I'm delighted to kick off this thread. I will try and get around to keep updated a Hall Of Shame for 2015 at the end of the thread.
For once it's not a Spoons from me but a GBG entry with a reputation, I can't actually think of a disastrous Spoons visited last year.
My worst pub of 2015 is the Port Street Beer House. It's a small run of the mill shop conversion with a selection of all sorts of beers. I was served a warm pint of sludge for £4.20 and had to ask for it to be topped up. Some people seem to have fared better but I certainly wouldn't go back to see if it had improved.