It depends, The Northern Hemisphere has been subdued to a lot of unfair criticism about it being "far behind" the standard of Southern Hemisphere rugby.
In all fairness, the Southern Hemishere always has a strong selection of teams, whether its the All Blacks, Springboks or Wallabies.
This constantly changes all the Time. Back from around 1997-2003, The Northern Hemisphere was more dominant with England beating the Southern Hemisphere nations in there Summer Tours, as well as them winning the World Cup.
Most people jump on the band wagon to be honest, everyone just goes a long with the same opinion though, they are still in the belief that the Northern hemisphere isn't just bad, but looking at some of the comments of other fans, they are terrirble.
Its always even, there will always be atleast one team from each Hemisphere that can beat the other side. Wales beat the Wallabies last November and they look the best side in the Southern Hemisphere now. France beat the All Blacks. A quick team put together in 8 weeks managed to beat the Springboks 28-9. Thats all in the past 4 weeks.
Like i said earlier its nearly always even, contrary to what some people say