With the release of the Microsoft (MSFT 0.37%) Surface Pro over the weekend, the obvious comparison is with Apple's (AAPL 1.27%) iPad. The already polarized masses are arguing either that the new device falls short of the iPad's tablet chops, or that the productivity capabilities mean Microsoft has redefined the entire space.

The one conversation that is conspicuously missing from the conversation is any comparison with the devices available from Google (GOOGL 0.55%). For as little as $400, you can buy both a Google tablet and laptop that arguably exceed the capabilities of the Surface Pro. Ultimately, for a significant savings over either the options available from Apple or Microsoft, Google is a legitimate alternative. In this sense, the decision turns on your desire to use the Microsoft productivity suite.

Microsoft joins the party
While Microsoft has long been the leader in productivity software, the release of the new Surface Pro marks only the second PC offering from the company. The device is essentially a laptop in a tablet form factor. This format makes the comparison with the iPad the most natural, given that Apple owns the full-size-tablet market. And despite many pros, the weight and weak battery life of the new offering from Microsoft make it easy to dismiss it as no iPad.

Where the Surface Pro changes the conversation is that it contains a full laptop processor and that runs a full version of Windows. Once you attach the additional keyboard, you get a fully functioning laptop in a tiny size. The Surface Pro may prove to be a bit heavy for the tablet market, but the target of the release is to propel mobile computing to the next level.

In terms of price, the Surface Pro starts at $899 with 64 GB of storage, jumping to $999 with 128 GB. The larger version is already sold out online, but without knowing the numbers, it's hard to characterize that situation as a supply or demand issue. From Apple, iPads start at $499 for a 16 GB device, while a 128 GB version runs $799, a full $200 below the Surface Pro of the same size. Of course, the MacBook Air starts at $999, running up to $1,199 for the larger version. If you think you would need either a MacBook Air or both that and an iPad to accomplish what the Surface Pro does, the price quickly becomes more reasonable.

The Google alternative
But if you're looking for a much -- and I mean much -- cheaper alternative, the combination of a Google Nexus 7 tablet and a Google Chromebook can be had for a combined $400. The Nexus 7 starts at just $199, and while we're now talking about a 7-inch tablet rather than a full 10-inch version, the Android tablet is not light on performance or apps. There's a reason the Nexus 7 is one of the leading non-Apple tablets out there.

The Google Chromebook is a fairly new entrant. It's the Google solution to the MacBook Air, for about one-fifth the price, depending on the manufacturer you choose -- versions range from $199 to $329. The device comes preloaded with various Android apps and relies on cloud access to the Google productivity suite for the bulk of its computing might. While this won't solve the problem for those looking to run Microsoft Office on their laptops, as more and more corporations and governments transition to Google Docs, this solution begins to make more sense.

The success of Google Docs, and the penetration that it has achieved, has been largely responsible for Microsoft's development of Office 365. This is Microsoft's cloud-based version of its productivity suite, as an increasing number of users wish to transition into the cloud. Some commentators have noted that for most basic operations, Google Docs is able to compete with Microsoft, but for really heavy lifting, Office remains the gold standard. Microsoft Excel, for example, has capabilities well beyond that of the spreadsheet app in Google Docs for intermediate and advanced users. Anyone wishing to do heavy-duty statistical analysis will find Google Docs wanting for certain critical features.

The verdict
In the most general sense, all of these developments should be seen as significant advances in mobile computing that will benefit consumers. As the number of options continues to increase, competition is likely to increase and advances are likely to occur. In the immediate term, Google provides a legitimate alternative to either Apple or Microsoft for a fraction of the price. Not surprisingly, the landscape remains somewhat static, with Apple providing the smoothest devices, Microsoft the most powerful software, and Google the most creative and affordable solutions. As Google continues to fire on all cylinders, the company looks increasingly attractive and should be considered a buy at current levels.