Seems that its just another lazy company (Cisco) that wont make a true windows 8 modern application until they deem it necessary. Seeing that probably 90% of windows 8 users are not on RT, they don't need a traditional windows 8 application in order to use their client. Cisco's Anyconnect application is what my office uses, but I have installed Teamviewer on my Surface RT, and on my work computer, and it works like a charm - a little slower than if I used the direct link through Cisco, but it works, and is fine for most tasks - especially if your not doing graphics intense work. The Anyconnect application works through the desktop on windows 8, which is probably why MS wont give Cisco the API's necessary to run their software. My guess is that Cisco is lazy - they want to be able to use their existing desktop software, and MS wont give them the info to do so - forcing them to re-write the code for a modern application, so its a little game of he said/she said. Hopefully they see the light, and make the damn app. Until then, Teamviewer will have to do.
I have windows 8 installed on my laptop, and really like the modern UI - maybe im in the minority with this, but I like it. I like the applications, the short cuts, the mouse hot spots, etc. Not sure why people hate it so much.