Only if you're willing to queue, but there's plenty of other places that dont require you to stand in line with all the tourists for an hour. Given how hot it is, there will be plenty of families out there, grabbing drinks from the food / drink trucks and letting their kids loose in the fountains (including us on Sunday).
As others have said there's loads of bright new pubs / bars / places to eat round Coals Drop Yard, as well as some great shops and it's VERY different from what Kings Cross used to be. There's also The Standard hotel directly opposite Kings Cross which has both a beer garden and a roof terrace.
If however you still fancy traditional pubs then there's still a few as you head into Bloomsbury such as MgGlynns (with pub cat) and The Boot.