Google has pushed out an update to the refreshed Nexus 7 which should fix the touchscreen sensitivity issues that some Nexus 7 users have been experiencing. According to Google's Paul Wilcox:
As a couple of you have mentioned, there's a new system update that's started rolling out for your Nexus 7s. This update does address the touchscreen issues discussed in this thread. If you're one of the people experiencing touchscreen issues, please let us know how it's going after you've received and installed the update.