I have gotten 15-20 ms higher ping as of late on EU_1.
It's probably your ISP routing you threw an additional hop or two so they can make money/because they're retarded. Do a tracert and see if the routing is wonky(ex. sending you to three states away when you live in Wisconsin). If it is, call your isp, ask for a higher-up, proceed with bitching.
Final step: Complain more because nothing gets done.