I'd say it's pretty normal, at least on JellyBean. When I check task manager, it usually says 650 - 700 MB with only like WhatsApp opened while the rest are system applications or tools, so I'd say it's pretty normal and not to worry about it.

 

That's alot

 

You shouldn't really shouldn't be worried about your ram usage. Android handles itself just fine.

Do not use task killers to try to free up more RAM

 

That's about what my phone on ICS uses at idle.

However, like Rxpert says above, Don't bother with task killers. Android, at least in general, can handle it's own RAM just fine.