The long-awaited Google Drive, a cloud-based file locker, is expected to launch next week after months of rumors.

A report from The Next Web, based on a leaked document provided by someone claiming to be a Google Drive partner, says that the service will be available for mobile, Mac and PC. The report also notes the service will start giving all users 5GB of storage for free.

That would be a definite blow to Dropbox, which is still the leading service in legitimate cloud storage. Dropbox users get 2GB of storage for free and then can pay either $10 or $20 per month to upgrade to 50GB or 100 GB of storage. It also matches the free 5GB offerings from companies and SugarSync.

Like other cloud services, Google Drive appears to be set up to allow users to make edits to a document on one device and have those changes update everywhere else. A previous Next Web report tipped that the Google Drive app would allow for editing via mobile app.

TechCrunch appears to have gotten its hands on a version of the Google Drive app for the Mac — thought it’s just an icon at the moment.

Writes the blog’s John Biggs: “I was able to log in using my Gmail account and I suppose I’ll have to wait to play with it further. It currently throws an error stating that “Google Drive is not yet enabled for your account.”

These are some of the strongest indications so far that Google’s drive is set to go, after several false starts. As GigaOm pointed out, rumors about the service first popped up in 2006 and have picked up steam four times since then. The latest round of speculation was prompted by a Wall Street Journal report in February that said to expect the product “in weeks or months.”

Google did not immediately respond to a request for comment.

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