Google Everflux

Remember don't go spreading any SEO myths that you believe may be true. Test it yourself several times on different websites before reaching any conclusion as there are other factors involved as well.
Within the past months, rankings within Google have become more dynamic, more fluid. They can change from day to day, what some people are calling Google Everflux. This is very similar to the old Google Dance we used to have a few years ago...when Google would update or refresh its index about once a month. Now Google is stepping out on that dance floor every day.
Over time old links you had are being dropped, as Google re-ranks their links and index. The whole fall-out from Google's paid link crackdown is still being played out as webmasters scramble to devise new ways to juice-up their links. Google is firing back with new ways to keep its index supposedly honest, an ongoing, turbulent battle that will probably get more turbulent. As new sites and links become important there will be a constant change in the rankings within Google.