As with everything, pubs can be awesome places that fill you with joy, good places where its nice to have a drink or two, places you're indifferent to, places where the atmosphere makes you uncomfortable, or they can simply be shitholes (although some of the best pubs are shitholes). The scale goes from 0-5 bad to good, 2.5 being neutral; for the most part we'll try to offer a better description 'cause you cant learn that much from just a number.
Any Pub that serves Real Ale is OK with me; any Pub that does not serve Real Ale will generally get less then 2 marks (unless there are extenuating circumstances) because in general such pubs are are contemptible.
However, I also find it dissapointing that the majority of pubs which do serve Real Ale tend to serve only big brand real ale, like, for example Wells and Young's, Greene King or Wolverhampton and Dudley. There are hundred of small breweries all over the country producing interesting and quality ales yet the only place we can rely on being able to try them is at CAMRA festivals or a few good pubs (like the The Marble Arch in Manchester, or the The Odd One Out in Colchester). Only selling big brand brewers reeks of laziness and is indicative of a lack of commitment, after all, variety is one of the most important factors. For that reason, any pub that does not serve at least one local or small brewery guest ale will not recieve 4 or more points without exceptional compensatory circumstances. Such as strippers. Or amazing pork scratchings.
Pubs will be organised geographically, either by country, county or around an urban centre (where justified).