There will be a server update beginning on Tuesday 17.04.2012 20:00 (GMT+2).
How long the server will be off can't be said for sure. Be prepared for about 2-4h downtime. There will be a complete re-install of the OS and all associated tools. We will upgrade to Windows 7 64 Bit (from XP 32 bit) and will then be able to fully utilize our 8GB RAM. This will help the database performance a lot.
Short version is increased performance on server side lag!
I am also hoping that it means a little more stability for US players, where a few extra database cycles can mean the difference between timeout/LD!!!!!