Put it into a box or somewhere that can hide the lights or turn it off totally.

What I did is take a Post-It sticky note, fold it so that it sticks on top of the router and folds over the "disco" lights...

Just received and connected the TP-LINK WDR3600, indeed the default LED light behaviour is redicilous, especially with the large blue LED lights this router has.
How could a product designer come up with this annoying behaviour? "Well, let's make everything as much flashing as possible."
Other routers also have flashing LED's mostly small and yellow, but they normally flash really fast when there is activity, so you notice their is active but it is not annoying.
I am glad that this routers is not in my bedroom.

System LED:
On - The Router is initializing or maybe has a system error.
Flashing - The Router is working properly.

This should be the other way around.

A firmware update so the user can setup LED status them selves would be a nice option.
Sticking stuff on the router is not a solutions.

You're kidding Guys, the led light is not a problem, the real problems are elsewhere... I mean into the firmware...

HiSpeed wrote

You're kidding Guys, the led light is not a problem, the real problems are elsewhere... I mean into the firmware...

Well, it's one of the first things I noticed after I powered on the router and plugged in the networks cables.
Finally got nice weather over here, so I haven't used it a lot.

It's offtopic but:
I can get the full 75/75Mbit speed from my ISP on wired devices.
Did not have any problems with browsing the internet, streaming media, downloading/upload files, torrents, usenet, and online gaming on Xbox Live.
Uploading 5000 files of just a couple of kilobytes (a Content Management System to my webhosting), goes fine also, it does not slow down other traffic on the router (I think something like that is pretty intensive for routing?)
WiFi range and speed seems comparable to my previous Linksys WRT54GL.
So far, the basic things a wireless router needs to do works OK (give devices a IP and route traffic to them, wired or wireless)

In the routers interface I noticed some things which could be more user friendly.
Problems I found so far with the latest firmware:
Time settings are not saved correctly, converts back to time zone China (instead of the set CET)

Connected a 2,5inch hard drive to test: is accessible as a shared folder and can read/write files.
But as I read in other threads: media server is a mess.
Sony Bravia TV can see the folder structure, but does not see any files (even while they're files on the disk that the TV can handle)
Xbox 360 sees some files, but it cannot play them.

And on my WD TV Live I see why: MP4 video files are served as audio file, so I only get audio, no video (WD also states: uknown codec for video and audio)
This works all fine if I just select my Windows PC with Windows Media Player as media server.

Well, and these forums are a mess... Spam bot messages everywhere, even while the first message you post is moderated by a admin.