Talking about storage capacities amongst the big tycoons should include a comparison of the capacities along with their limitations. This sort of insightful comparison will be fair and impartial. However, the frequent updates in the form of rumours, proposals and facts often makes it difficult to isolate what matters. As such, here is my take on what I know so far than can hopefully help void that gap.
First off the bat, file-sharing services like Windows SkyDrive, much like Google Drive, lets users store information for personal use. SkyDrive, although in Beta mode, has an excellent feature that lets users make folders public. For instance, if user John, for arguments sake, needs to share a file with Jane, then John can accomplish that without having to let Jane access his personal email.
Recent windows vista blog news tells us that they SkyDrive has doubled storage capacity to 1 GB from previous 500 MB. This is ahead of Google Drive, but perhaps due to the fact that Google Drive is presently offering its services through limited invitations. Hence, it would make more sense to compare it to Box.net, which already offers 1 GB of storage.
Secondly, in terms of email storage, we have Windows Live Mail providing 5 GB, but with a 10 MB file size limitation for emails that might not suit heavy users.Gmail, on the other hand, offers less than 3 GB and claims to be expanding on that scope according to their blog. Last, but not least Yahoo, still offers unlimited email storage. However, unlimited refers to Yahoo providing unlimited service as a privilege as long as its not exasperated or otherwise abused by users.