How Gmail's new inbox affects open rates

In recent weeks we have been seeing changes to the Gmail inbox.  The idea... to help users sort their cluttered inbox into 5 categories: Main, Social, Promotions, Notifications and Forums.
Under the new "Promotions" tab, where we should expect our emailings to go from now on, we find some "extras". advertisements disguised as email marketing. So it seems that doing the user a favour was not Google's only objective. However, it is not a bad idea, given that the user who clicks on "Promotions" expects to find this type of information. In principle it seems a good initiative, so that the user does not find himself lost in the middle of the confusion of contents in his inbox and can Separate your reading space from personal mail, notifications and commercial communications.. However, the worrying thing for us, email marketers, is whether the user will actually make use of the "Promotions" tab or ignore it. as is often the case with commercial communications. The second case could be natural user behaviour, however, in the case of email, the user has allowed and even demanded these commercial contacts and for this reason their interest in this tab may grow.


Many of us were already beginning to wonder how these changes would affect our opening rates and yesterday, Mailchimp provided data on this influence. It is too early to fully understand the data and the real impact of these changes, Gmail open rates in these first weeks show a slight drop.

Source: How Gmail's New Inbox Is Affecting Open Rates, by Mailchimp - 23 July 2013
This is not a substantial drop in rates, but it may indicate a downward trend. One aspect to consider is the novelty of the change and that this initial use of tabs may just be a response to a user curiosity which may fade over time. We will have to wait some more time for reliable data, when the novelty factor will not influence user behaviour.
What do you think? Do you think this downward trend will be corrected when the user gets used to using the tabs.or, on the other hand, do you think that This drop in openings will be accentuated, due to the new structure?