I would say now might not be a bad time; if you've got a Honda that you've gotten 75k out of and can still get $10,000, then take that $10k and put it towards a new car while the car is still worth something. Sure you could "run it into the ground" and drive the same car for 20 years, the last ten of those twenty of which would be when the car is a pile of *****, but it comes down to what you want for yourself and if you're comfortable always driving a pile of *****. Driving it into the ground is no guarantee that it will be cheaper either. It's all fine and dandy til it needs a $2k engine or transmission, or $500 every month to stay afloat, or $1k AC compressor.
I'd say take the $10k and run, put it towards a new car with a warranty with a guaranteed $0 a month repair costs and a payment you can budget for, and with $10k down you'll be better off with the car in that you won't be upside down on the new one if something happens and you need to sell. What's the point of running a car into the ground? So you can drive a pile with no planned payment but a ticking time bomb of repair costs at any time, just so at the end of the day after driving an unenjoyable pile of junk for X years when it finally does crap out for good you can have nothing to put down on a new one so you can be upside down or with a large payment on a new one?
Figure it this way, you can do it one of two ways:
1) Run current car into the ground until, say, 2015. Over the next five years pray that you can save up $10k for a down payment (since you won't have a car payment now) for a new car for when your Honda is worthless junk and leaves you stranded for the last time, forcing you to buy a new car whether you really are ready to or not since you never know what will pop up or where you'll be financially when your car does take it's final crap. Spend X years driving a piece of crap, gambling everyday on repair costs you may or may not have.
2) Sell/trade car now, and buy a new car with $10k down. Have a car payment, but also a warranty so no surprises and you can budget your money more easily knowing you won't have a big surprise repair bill (or multiples). Since you have a payment, you won't really be able to save for a downpayment above, but if you trade this new car in again when the warranty is up (which by then should be about when you pay it off), then you can figure it would roughly be worth $10k (for example's sake) so just like above, you've got $10k to put towards a new car, except this time you know you've got the money there, and can trade it at a time that is comfortable for you, not when you are forced to. Spend X years driving a nice new car that's not a pile, and have a nice amount of change to put towards another new one in 2015 if you want.
In both the examples above, the net result is the same if the situations are ideal--both people end up with $10k to put towards a new car, except one person is going to get forced into a new car when it may not be good for them, drive a piece of crap for a bunch of years til they hate it, and gamble on repair bills while trying to save for the day the car does crap out, while the other person will always be in a car that's nice, has a warranty, and has no surprises financially or otherwise.
Trade the car while it's still worth something.
FWIW, you can always trade a car, they just won't give you much for it as the mileage/age creeps.