…remote control was either difficult or expensive.
You could choose the Microsoft approach.  You could use the RDP solution from any client.  But if you wanted to actually connect to a desktop, that system needed to be running a “professional” version of the OS.  That meant that you could have remote control from Microsoft if you paid them first.
But if you refused to pay the Microsoft tax, you could always pay Citirix for the right to use their remote control tool.  Yes, it worked well.  And it didn’t require a special version of the operating system.  Instead, you just paid a license to Citrix and you could help whoever you wanted to help.  But licensing was horribly complex.  You had to have a license for a certain number of supported desktops or every desktop had to have a license of its own.  So if you wanted to get help, you had to set stuff up BEFORE you had a problem.
Fortunately, you could always roll your own solution.  You could install a VNC client and server on the systems that you wanted to access remotely.  And if you wanted real security, you could always use an SSH client and server to make sure that your connection was encrypted.  It was so easy to do that… OK, it wasn’t that easy to do.  If you had an uber-geek for a spouse (or any teenage child could substitute), then you could brute force your way through the maze of complexity.
So the choice was simple: build a terribly complex solution or pay for someone else to do it for you.  Now you have another option: Chrome Remote Desktop.
Google is building the Chrome OS.  And they need to have a way to provide for remote desktop administration.   It has to be secure and it has to be simple to use.   So how do you do both?  You build a tool on top of other infrastructure that already exists.

1. You need a rendering engine that can run anywhere.  So build it on your browser.
2. You need a transport mechanism that is easily secured and can pass through almost any firewall.   So build it on secure HTTP (https/443).
3. You need an extensible platform that can encode almost anything into an XML stream.  So use jabber (i.e., xmpp) as the transport and stream platform.
4. Finally, you need a well known means of connecting users to each other.  So use GTalk as the central nexus for interconnecting people.

In the end, what you have is a secure infrastructure that can easily be implemented via Google accounts and extensions to the Chrome browser.
I’m still a little leery of anything that is so simple and easy to use.  But I think that this one may be a real winner.