Why not? If you made a backup product called "Windows Backup" (or more relevant to this example, a collaboration product for Microsoft Office called "Office Duck"), Microsoft will definitely go after you for trademark infringement. Why should it be any different for an open source project with a registered trademark?
'In addition, you may not use any of the Marks as a syllable in a new word or as part of a portmanteau (e.g., "Gitalicious", "Gitpedia") used as a mark for a third-party product or service without Conservancy's written permission.'