I'm in the not worth it camp, if the idea is to actually spend the night in Paris. As pointed out by others, you've got to be at the airport at 7am for a 10am flight (and if this is your first time at CDG, even 3 hours will not be stress-free!). My experience is with T1 (Star Alliance); could be different elsewhere.

If you spend the night at the airport, you'd be looking at something like this-
Land 6:40pm
Pick up bags 7:05pm
Get to hotel via CDGVAL 7:20pm
Check in, take shower, back to RER... maybe 8pm
RER to Gare Nord, arrive about 9-9:30pm

I'd say you'd have 2, maybe 3 hours tops in Paris before wanting to get back for some sleep. Seems rather rushed to me, but sure, you could do it.

Just remember, if this is your first time flying out of CDG, it is not an easy experience, at least not in T1. Security is at the gate, with really long queues, and prior to that, passport control can be another huge amount of time.

Someday I'm going to get a special T-shirt printed up, with a photo of T1, captioned "Airport by Escher."