The 'reality' that surrounds us is taken in through the limited senses we have (we frail creatures, can't even see radar or thermal emissions) - and registered in our consciousness inside our brain, perhaps without full fidelity at all times.
Therefore, everything we perceive as 'reality' could arguably be unreal when compared to video of the same senses. Imagination has a strong influence on what we perceive (ask 10 different witnesses to a crime to report what they saw, and you'll get 10 different realities - even though they were observing the same event), as well as conditions that trick our senses (mirages and slight of hand).
Is cyberspace real? As real as anything else we take in through our senses, and think we know about the world around us.
Computer networks are not just about communications - like radio or telephone systems - but the computers in that network allow for persistence within the confines of unique addresses on the packet switched network. Persistence allows the formation of virtual spaces at these network locations - that can be as simple as a threaded message board, where conversations can form a complex web of shared history and culture, to more complex forms including 3D multimedia simulations that mimic space as perceived by humans in the 'real' world - in both places were multiple participants can form community. To the participants in these virtual spaces - it holds as much importance as other spaces within their lives - perhaps more so with the demise of the public spaces - the local bars, parks and so on that formed a 'third space' (first being home, and second being work) who's easy access was lost with the advent of suburbs and the fast food drive-through (borrowing heavily from ideas put down in Howard Rheingold's "The Virtual Community - Homesteading on the Electronic Frontier").
These virtual spaces allow people to quickly find like minded people, form alliances, and get things done. These spaces have significance - they can spill over into the real world - such as the 'Arab Spring', and change the face of countries and the world. They can also be misused and lead to group-think, and victimization of its members (ask Mante Teo about that - or your local Troll).
The value of cyberspace outweighs the desire of lawyers, regulators and governments to find simple answers to complex issues.