Those who think that the BEST project’s additional surface temperature data will change global-average temperature results significantly should have a look at this plot —
The GHCN stations were selected completely (pseudo)randomly, with no attempt to maintain uniform global coverage.
What you can clearly see is that all of the “1 out of 10″ results agree reasonably well with the NASA results. In fact, most of them show a bit more warming than the NASA results do. (So much for idea of NASA “cooking the books” to exaggerate the global-warming trend.)
So if throwing out 90% of the currently available temperature data doesn’t change the results very much, then adding a bunch more data (data that are largely redundant, due to the long temperature-anomaly correlation distances) is highly unlikely to have a noticeable impact on the results.
Expecting the BEST project to upend the current global surface temperature record would be rather like tossing a coin another 1,000 times with the expectation that the head:tail ratio would start to deviate significantly from 50:50.