Here are differences that might be overlooked by writers making the transition from the seventh edition.
Books and Other Printed Works
The principles behind in-text citations in MLA style are unchanged. A few details have been added or clarified, though:
Print book with one author:
Eighth edition (the new way):
Jacobs, Alan. The Pleasures of Reading in an Age of Distraction. Oxford UP, 2011.
Seventh edition (the old way):
Jacobs, Alan. The Pleasures of Reading in an Age of Distraction. Oxford: Oxford UP, 2011. Print.
An article from a scholarly journal:
Kincaid, Jamaica. “In History.” Callaloo, vol. 24, no. 2, Spring 2001, pp. 620-26.
Kinkaid, Jamaica. “In History.” Callaloo 24.2 (Spring 2001): 620-26. Web.
From "What's New in the Eighth Edition" on the MLA's website:
"The eighth edition of the MLA Handbook, published in 2016, rethinks documentation for an era of digital publication. The MLA now recommends a universal set of guidelines that writers can apply to any source and gives writers in all fields—from the sciences to the humanities—the tools to intuitively document sources."