Running a web app in Grails vs Django
i think python tend to have lower hosting requirements (i.e., grails needs a jvm, and most el-cheapo hosts dont provide one, where as they usually provide python support). Plus google app engine supports django (to some extend). 
But if you got the dough, grails is so much better imho.
I'm currently in the planning stage for a web application and I find myself trying to decide on using Grails or Django.  From an operation perspective:

Which ecosystem is easier to maintain (migrations, backup, disaster recovery etc.)?  If using grails it'll probably be a typical tomcat + mysql on linux.  If django it'll be apache + mysql on linux.
Does django or grails have a better choice of cheap and flexible hosting?  Initially it'll probably be low bandwidth requirements.  I'm not sure about the exact specs required, but from what I've been reading it seems like django would require far less server resources (even 256MB server is ok) than grails.