I bought a new bike, and have ridden twice in two days, and sitting on the seat the second day was pretty painful. I didn't notice the soreness till I sat on the saddle.

I am hoping(!) that this soreness will abate. Please someone tell me that it won't last long.

It depends. Is the seat bad or are you just unused to riding a bike for a long time?

Well, I haven't ridden for a while. I guess it has been about 15 years.

Then it's probably that. Although the seat may have something to do with it... do you feel uncomfortable in the seat or do you just get the pains towards the end/after the ride?

Yeah its almost definetly the lack of riding. So, even if you need to get a better seat, it will probably never bother you nearly that much after a few long rides.
If you want a new seat, get one with a center channel/cutout.

Been riding for 15 years and I hate new saddles. Not only the butt has to get attuned, the saddle has to wear in aswell. Centre channel works, but stay off the Big "Comfort" gel saddles. Fine for a couple of miles but after a couple of hours really painful.

Well, it has a center channel cut, but I never thought that the seat might also have to break in a bit.

I seem to only be sore right on the pressure points where the pelvic bone sits on the saddle. I just hope that it doesn't last long, because I'm wanting to go out right now, but I don't think I could.

Well, give your posterior semi frequent breaks by standing up a bit. Also stand up over larger bumps to absorb the shocks

My seat will never break in, but not becasue it's bad quality.

Just like a new pair of jeans, you'll get used to the seat and the seat will start conforming to you. With time both parts of the system will be synchronized. I took a 3 month hiatus from cycling (thanks to all the Southern California rain this year), and the first couple of rides this spring was the proverbial pain in the butt.

Padded riding shorts.
And when not riding, get spankings for being lazy, this is good motivation and it toughens your posterior.
Pitching the saddle can distribite the weight better, mine is slightly tilted up in front, this lessens the pressure on the bones underside, and for hand\palm pressure reduction.
Some people can't stand pressure foreward, cutouts and tilting the saddle nose down works.
Riding a bike with the seat too low\very upright fashion will have more weight on the saddle.
I've tried several styles of seat and prefer a scoop at the back, it seems easier to adjust your position on the saddle when riding hours or moving around on difficult terrain.
This is saddle #6, finally something that works for me..ahhhhh.

Agreed, a scoop on the back makes a very comfy seat

I went out today for the third day in a row. I raised my seat a few inches (trying to find the ideal height) and found that the pain wasn't as bad as yesterday, although it was still there.

I think that my problem is a combination of my butt being out of shape and the seat being too low.

What a small world. My gf's sister lives in poco. You have some nice parks and trails near ya ...

I must be lucky, my butt seems to be able to take any seat without pain. (so far)...

I can't really get super comfortable on any bike seat, but it's not painful. I'd rather sit on my bike with the Specialized BG seat for 8 hours than in a car seat.

Well I shouldn't say it is a joy, but no seat kills me

Yeah, I've been riding on the (Traboulay) Poco Trail, which is just a few minutes from my place. It isn't exactly challenging, but it is peaceful and has beautiful scenery. Right now, I'm concentrating on getting in shape, and the trail is perfect for that.