Given the 8MB size, it is expected to be mainly a bug-fixing update and will not include any user-facing changes. You can check for the update by going to Settings << About Tablet << System updates << Check now.
You can also download the update using this direct URL from Google and flash it via custom recovery or using ADB Sideload command.
According to reports on XDA, even this update does not seem to have fixed some users’ touchscreen woes. If you have gotten the update, do let us know your experience in the comments section.
In related news, the LTE version of Nexus 7 (2013), which went out of stock from Google Play US, has returned in the stock. If you were not able to make your purchase yesterday, you can try now.