I wouldn't advise massive autoroutes in any of today's layout packages. By "massive" I mean placing the components and calling "autoroute all". By the way, placement should be done manually as well. However, autorouting individual nodes and segments often produces good results (at least in OrCAD and Protel).
Especially this feature is usefull by design reuse. U manually route any repetitive section of PCB by taking into considerations related with EMI or SI and auto route other repetitive parts.