Hi,
I've been riding a Trek hybrid for quite some time--about 8 years--and while up til now, I didn't ride much at all--mostly just relaxing cruising around town on rather rare occasion--I've been riding it quite a bit more lately, specifically using it as a main source of exercise, and want something new. Initially, I was thinking I'd just go with a new hybrid, like the Trek FX---my current one is more of the "comfort bike" variety--the FX looks to be a faster, zippier hybrid, but more versatile than a road bike, for those times when I want to go riding alongside my 7 year old in the park, or casual cruising around town.
However, now I'm wondering if I should be looking at a road bike, or maybe even a cyclocross?
As I say, my main intended uses are:
1. Exercise, and where I'm riding is right alongside plenty of roadies (who are of course flying past me!) on the lovely bike paths around Pasadena, CA, including the Rose Bowl, etc.
2. Casual riding with the family and exploring around town, sometimes hitting dirt or rough pavement (but I have no intention of anything resembling off-roading/mountain biking)
3. Climbing. I add this simply because, when I walk out my front door, I am faced with significant hills in every direction! I do it now on my "comfort bike" and I just can't wait to be on something more suited to the terrain...

So, does that still add up to a better hybrid than what I currently own being the best choice? I want it to be my sole bike, whatever it is--I will likely give my old hybrid to a nephew when I get a new bike. Or would a road bike or cyclocross make sense for my uses? I want to be able to go faster, take longer trips, and get a serious workout, but also want versatility.

Any 2 cents appreciated!