Of course, a Gigabyte 'isn't what it used to be' and we do get a bit blasé in 2014, but 15GB should still be more than enough for most people, at least providing they don't want to store all their media up on OneDrive as well (something which has been rumoured for a while and even implemented by a third party).
From the OneDrive blog post:
...today we are announcing the following:
1. OneDrive will come with 15 GB for free (up from 7 GB)
Our data tells us that 3 out of 4 people have less than 15 GB of files stored on their PC. Factoring in what they may also have stored on other devices, we believe providing 15 GB for free right out of the gate – with no hoops to jump through – will make it much easier for people to have their documents, videos, and photos available in one place.
2. All versions of Office 365 will come with 1 TB of OneDrive storage
Soon you will get 1 TB of OneDrive with your subscription to Office 365. This means you will get the power of the world’s most popular productivity suite, Office, along with apps for your laptop, smartphone, and tablet, plus an enormous amount of storage, for an unbelievably low price.
In addition, the post goes on to describe lower charges for additional storage needed, matching Google's Drive charges more or less exactly:
3. We are dropping storage prices by over 70%
Of course, we also want to give you as much flexibility as possible, so if you need more storage, but don’t need an Office 365 subscription, we will also still provide monthly subscription storage options – at dramatically reduced rates.
The new monthly prices will be $1.99 for 100 GB (previously $7.49) and $3.99 for 200 GB (previously $11.49).
All of these updates will take effect in the next month. For current subscribers, you are all set, you’ll automatically be moved to the lower prices.
Given enough bandwidth to get access to cloud storage (not always a given), $2/month for 100GB is astonishing value, given the amortised costs for (for example) buying a local hard disk, running power to it and replacing it every 6 years - it's clear that, even with economies of scale in their server farms, Microsoft and Google are still not really making much of a profit (if any) from a well used cloud storage tariff. For these companies, it's more about the hook to get customers and companies into their services generally (e.g. in this case to Office 365).
So, hopefully, you should see your 'free' storage, listed on OneDrive, automatically increase in the next few weeks. Of course, I, and many others here, took advantage of Microsoft's offer to upgrade for free to 25GB two years ago (referred to here), so nothing will actually change, but new users will definitely benefit!