Here 's an excerpt from a nice article by Ronan Guilfoyle taken from his blog
"...The developments in the rhythmic language of jazz – and by that I mean the expansion of rhythmic techniques available to and used by jazz musicians – have been enormous over the past twenty years. I remember demonstrating the playing of ‘All the Things You Are’ in 7/4 in the early 90s at various jazz schools and getting reactions that ranged from surprise to complete incredulity. Now such things are commonplace – no longer exotic, 7/4 is indeed the new 3/4, at least among young musicians – it’s that ‘other’ time signature you go to when you need a break from 4/4. And that’s just the tip of the iceberg, something that’s considered pretty mainstream these days – in addition to that you have a plethora of techniques used by various musicians ranging from the additive rhythms of the Balkans, to metric modulation techniques (derived from Indian music, or the Miles 60s rhythm section, or even the work of composers such as Elliot Carter), to playing in odd metres. And of course many musicians use many different aspects of these things in various combinations, exploring a bewildering array of rhythmic approaches and techniques.
There are various reactions among musicians to all this new activity ranging from enthusiasm and excitement, to fear and dismissal. Where musicians are positioned in this reaction range usually depends on their age and experience. For younger musicians this new rhythmic landscape is what they’ve come to expect, to older musicians it’s often a scary place to be, depriving them of the rhythmic underpinning that they’ve based their entire musical lives on. But like it or loathe it, the genie is out of the bottle as far as this development is concerned – complex rhythms and much wider variety or rhythmic techniques are here to stay..."
Read the whole article here: http://ronanguil.blogspot.gr/2010/05/rhythm-people.html