The online cloud-based collaboration services market is heating up. Established software vendors -- think Google, Microsoft and IBM, as well as new entrants to the space -- are building impressive client lists that include large enterprises across the vertical spectrum.

This isn't just vendors trying to one-up each other -- there's a real and growing market demand for these tools. A recent Forrester survey found that more than 56% of software decision-makers are using or would use software-as-a-service (SaaS) offerings to replace or complement their existing collaboration technology.

Why are online collaboration services so appealing? Because SaaS gives business leaders the following three advantages:

1. Tools that make the business more agile and responsive. As Gap and Netflix recently demonstrated, customers who are informed and empowered with easy-to-access information can force a company to quickly change a strategic decision. To respond effectively, businesses need tools that allow employees to share information among themselves as well as with partners and customers. Online collaboration tools provide a centralized workspace that allows all participants in a company's ecosystem -- suppliers, partners and customers -- to work and innovate collectively.

2. Features and functions that evolve as the business world changes. Business leaders often tell Forrester that their business' communication and collaboration technology is sorely outdated and that they can no longer afford to remain stuck in the world of three-to-five-year refresh cycles. Online services can solve this problem. In fact, 60% of business leaders who currently use SaaS tout faster delivery of features and new functions as its greatest benefit.

3. Technology that easily supports a mobile and remote workforce. With 66% of information workers in North America and Europe working remotely, working outside of a corporate office is the new norm. IT leaders must be prepared to equip these employees with tools that keep them connected and productive on PCs, smartphones, tablets and more.

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It's no secret that online collaboration services vendors, large and small, seek to provide robust toolsets that address either a specific need or set of business scenarios. The bulk of these vendors, however, simply aren't seeking to deliver a comprehensive set of collaboration services such as email, document workspaces, real-time technologies and social tools. Rather, they are building a set of interconnected services which prominently feature file sharing as a way for businesses to interact with internal and external constituents. Forrester refers to this as a "cloud collaboration ecosystem."

Unsurprisingly, these offerings intrigue IT leaders while raising many questions that aren't simply about which vendor has the right feature set or collaboration scenarios -- like activity streams -- but are more fundamental questions about the viability of these offerings, such as:

1. Are these services enterprise-ready? Regardless of the size of the vendor, Forrester often hears from clients that they're not sure if a given offering is "ready for prime time." These IT leaders are unsure if online service offerings have sufficient support services and contractual terms for enterprise clients, infrastructure to scale to large deployments, and the policies and procedures that allow an enterprise to remain compliant.

2. How secure are these services? Many legal and security professionals working with IT pros are skeptical about security in the cloud, including data encryption, authentication models and identity or access controls. They also raise questions about the physical security of data centers and how vendors will address removing client data from retired servers.

3. Do these services integrate into my environment? Today, on-premises collaboration platforms are deeply intertwined with the computing infrastructure of many enterprises. Fundamental questions for Forrester clients include: Are the services customizable, integrated with legacy applications, localized into multiple languages for a multilingual workforce and accessible on the various PCs and mobile devices that workers use?

4. Are these vendors even committed to online services? Before deciding to make a service a part of their collaboration strategy, many leaders want to know if the vendor (or its offerings) will be around for the long haul. When it comes to large, established vendors, IT leaders also want to know if the vendor is serious about its online service -- or simply treating it as an "experimental" or "one-off" project.

Forrester has been discussing the immediate need for business leaders to get in front of their mobile, always addressable workforce for a while now. What we haven't stressed as much is the need to build collaborative frameworks to include the rest of a business' ecosystem in the conversation: channel partners, suppliers and customers. That means IT leaders must find ways to get information to and allow interactions between groups of people who are spending time beyond the corporate firewall. That's a great argument for the cloud, right?

Our survey data indicates many agree: The majority of decision-makers at organizations deploying collaboration software indicate they either currently or plan to use collaboration SaaS within the next two years. So, here's the pressure point on vendors that will be critical to the success or failure of online collaboration software: From a fundamental standpoint -- security, compliance, customization and integration -- are these vendors ready to handle this swelling demand?