How much is the cloud market worth? According to UBS, as printed by GigaOM, rather a lot - and it's going to be worth a whole lot more,.

>In fact, that question should be rephrased - how much is Amazon Web Services worth because, by UBS's reckoning, Amazon has already grabbed a massive slice of the cloud pie.- UBS estimates the servers and storage part of the cloud market to be $5-to-$6 billion currently, so it's not a small pie. Amazon Web Services has around $600m of it - so, more than 10 percent of the current market. And in an emerging market like cloud, the leading player is going to score very hghlly, its nearest competitor, Rackspace, is some way behind, so Amazon is going to rack up some hefty customer wins as cloud penetrates the enterprise.

In fact, UBS estimates that Amazon Web Services is going to be a billion dollar company within a couple of years,  going on to bring $2.54 billion in revenues by 2014. That's an astonishing growth for a company that's just a subsidiary of a larger corporation - and one that took nine years to show a profit, AWS was only launched in 2002, so that's an astronomic rise.

But that's only half the story, the size of the whole cloud market (including services) is estimated to be $22 billion currently and according to IDC research could grow to $55 billion - another indicator how quickly this market is changing,

It's clear that cloud technology is no longer something discussed at conferences that has little relevance for the modern business but is going to have a significant presence. What's going to be interesting to see is how the other vendors try to stop AWS walking away with a sizeable market lead.

The recent OpenStack initiative from Rackspace showed one way that AWS can be scaled back - certainly the proprietary nature of Amazon's offering is an inhibiting factor and the recent contretemps with Eli Lilly demonstrated a willingness to negotiate hard - a stance than tends to work when you're the dominant player, wonder whether that would hold if the market got more competitive.

It's certainly going to be an interesting couple of years for cloud watchers.

Follow Maxwell on Twitter