Yeah 4e is actually less reliant on the "trinity" then other editions, because it's more feasible to survive without a healer. Your still more efficient if you have a healer of course, but unlike previous editions not having one doesn't mean that your dead in the water.

Originally Posted by Fnord
Also, you don't have to bring the trinity when playing D&D 4, it is just recommended. In the last campaign that I participated in my party consisted of 3 strikers and a controller, and we did just fine (when the encounters were designed for parties of our level).