Google has added a new setting to your Gmail account, which allows you to revert back to text buttons, instead of the icon-style buttons found in Gmail after the redesign.
To revert from icon buttons back to the familiar text buttons, log in to your Gmail account and navigate to Mail settings (gear icon in top-right corner > Mail settings).
Under the General tab, there will be a new option titled Button labels. Change the setting to Text, then save your changes at the bottom of the page.
Easy-enough change, right? Gmail users should have the setting available for them right now. I was able to change the setting under a Google Apps account, however some Google Apps users are reporting the option isn't available for them as of yet. Give it some time to roll out if you aren't currently seeing it available to your account.