As far as the PS3 versus standalone pricing goes, that’s because the PS3 is subsidized. Game consoles always cost more to make than they sell for, as the company gets back money in licensing fees.

The drive in the standalone player is probably the same (I mean, it’s Sony, so you’d think they’d just buy a ton of the same parts), but the fact that you need the internet or burned DVDs to upgrade the firmware does not make it the same. The internal components are completely different. That BDP S-300 does not have the Cell processor inside, which is the source of the PS3’s crazy decoding ability. The PS3 simply has the flexibility to upgrade with every spec increase, because it has the hardware under the hood to. They had to add a 2nd picture decoder for PiP. Done, since the bluray decoder in the PS3 only took up 3 SPEs. It was fairly easy to tack on another decoder in the other 3 SPEs. It has enough memory for downloads (BDLive).

As far as future price drops go, I’d hedge my bets on the PS3 dropping sometime in Oct or Nov, perhaps earlier if the 360 drops in price (I was going to say E3, but they just upped the value of the 80GB bundle by adding in a $50 Dualshock3 instead of the SixAxis). The PS3 is the bluray leader, and Sony is pushing it in order to get Bluray and the PS brand into every living room. The standalone players are designed to make a profit, and won’t drop in price until costs have come down [which, incidentally, could be soon since the laser was just decreased in size].

The only downside of the PS3 is that it doesn’t support DTSMA and one other lossless codec (DTS HD?). So if you really want those codecs, you’ll have to get a standalone player, or wait until the PS3 gets a firmware update to allow those (I’m sure it will, it’s just on the bottom of the list).
References :

LA times had an article a few weeks ago. Prices for BD players are going to go up and Sony is going to push the new profiles so older machines wont play the disks that will be out by Christmass forcing everyone to re-purchase.

I have put a link below to the article.
References :
http://www.latimes.com/business/la-fi-player20feb20,0,6072978.story