One of the core things about Display Port that many are missing is that displayport does not require any licensing fee's to use. It is free to implement. HDMI requires a usage fee because of its proprietary license.
DisplayPort shares many of the same benefits of HDMI, picture quality is comparable to any of the digital interfaces, and has no silly usage fees.
It is starting to be used, so you should start seeing more and more of it. Dell is now putting in it in by default in some of their desktops for the built on video. I have it on my work computer. I would not go out of my way to get it right now, but it is part of the future. It does have advantages over other interfaces.
Quote from : http://www.tgdaily.com/content/view/33161/118/1/2/
This is a growing concern in the industry. There are enough talented people working on video standards today that the need for a uniform base is required. So the question becomes: is the specification in the public's domain? Can any corporation just sign up and use it without paying royalties? I was surprised to learn that most popular forward-thinking interconnects today contain some components which are still not free. DisplayPort is the only standard which offer truly free use. The HDCP encryption protocol used by DVI, HDMI, UDI and was recently added also to DisplayPort as an option, requires royalty payments. Philips' PDCP encryption protocol, currently used only by DisplayPort, is not only stronger, but it is also free.
The push is definitely for open, free standards. The newest member of the club and the one recently accepted by VESA as the new standard, DisplayPort, addresses that fact throughout its entire design.
EDIT: This is more from a manufacturing standpoint. From a user standpoint, they will use whatever becomes most popular. The average user doesn't care what the details or the politics are, just as long as it works easily for them. DisplayPort will fail if people decide not to implement/use it.
I have a monitor with display port on it. If it become commonplace, cool, I have it and can take advantage of it. If not, I got 2 dvi, hdmi, and vga to get me through. There are multiple analogies of user adoption and technology options.