I think this problem could be by my side. When I log in, everything is fine. After 15 minutes of playing my fluct raises to 22m/s or more. My internet connection is working well, so this isn't the problem.
My machine on which I'm playing is a Acer Aspire 5735z Laptop, Win 7 Ultimate(32), Dual Core 2.00Ghz, 4G RAM, Intel GMA 4500 video chipset. It is connected to internet via cable, wireless module is turned off.
Get that on occasion along with a percentage of loss/lag.
Restart router and computer, if that doesn't work then wait it out for a bit. ISP's could be doing maintenance, your line could be a bit unstable too. If it carries on too long, contact your provider.
I'm having 46 m/s flux, 40%+ lag, and double digit loss. I'm going to blame it on the beta for the moment since my internet is perfectly fine and I never had an issue prior to 4.87.