It’s going to be an interesting summer for Dropbox and Box in light of Amazon(s amzn) Web Services’s new Zocalo enterprise document sharing and collaboration tool. If the phrase “enterprise document sharing and collaboration” sounds familiar, it’s probably because you’ve been reading about how both Dropbox and Box have launched these types of offerings in recent months as a way to distinguish themselves in a crowded file-share-and-sync market.

With Zocalo, Amazon is essentially adding the capabilities of Dropbox and Box to its own platform as it attempts to dominate enterprise IT.

As analyst Janakiram MSV described in a blog posting on Gigaom Research, Zocolo will allow users to edit their documents in the cloud sans Microsoft Office, and any comments or edits made in the cloud can be translated over to a Microsoft Word document if the person happens to use Word to open the same file on his computer…