Sorry for late reply (and for poor english).
I'm triyng just in this day, to use an EntitySystem for large game development (ok, i'm planning to use it in a small game, but just something like RPG).
I'm testing Artemis and using AndEngine as graphic engine for now.
the Component entity systems architecture is a little different for my way to think at software.
No big classes but small components
big separation between data and logic
great also for team development because every system have to manage only his part of logic.
here's a link to a good article about entity systems: http://t-machine.org/index.php/2007/09/ ... nt-part-1/
here's the link to Artemis framework (small, fast and good): http://www.gamadu.com/artemis/
The only think, i have separated the business logic (all business systems) who are running in a separate game thread, and the rendering system (called on Scene onUpdate) so this systems are synchronized with a mutex object to avoid problems (IE: the expire system can remove an object just when the render system is about to process it, and this result in some error).
For me it's a bit hard to start thinking to entity, components and objects instead of usual way like, mobile class, monster class, player class, bullet class and so on.
But the first result seems to be good and the way you can use component to add behaviours to your system is really simple and useful.
(i don't have even a playable demo for now, just expect to have the basic components ad some simple system to create some a simple playable demo app).