Glad to see Vergent picked up this thread over here. I hear that Nunavut Flasks measured by NOAA are picking up with methane. On the other hand there was a recent cruise in the Laptev Sea that was inconclusive about the ESAS.
I saw a few minutes of this NOAA talk on May 19th, casting doubt on large ESAS emissions, in terms of a ship measuring CH4 well offshore in the Laptev Sea. http://www.esrl.noaa.gov/gmd/annualconference/abs.php?refnum=107-150406-A
Shakhova is also quoted in this NOAA paper on Carbon-Tracker Methane. The paper suggests no strong trend in the ESAS yet if you read some of the details: http://www.atmos-chem-phys.net/14/8269/2014/acp-14-8269-2014.pdf
In the May 19th talk, the argument was made that rising sea level will stabilize methane in the ESAS since the pressure would rise. However that seems to be a relatively small negative feedback. It was also mentioned that by the time we detect a clear trend it will be too late to stop it. Also, methane extraction activities in the area could contribute to speeding up the release.