It being removed has no baring on PS2 compatibility. As someone pointed out, they're planning on having a PS2 software based emulator.
It'd be a nightmare if somehow the source for that emulator leaked. It'd be a dream come true for PC based software emulators of PS2 architecture.
Also, the price drop is rather marginal with the PS2 chip removed. Their mention of the PS2 chipset making the system cheaper is a smoke screen by Sony to hide the real reason for price drops. You see, the removal of a PS2 chipset is in fact costly to Sony. Production and new silicon platforms cost the company more money than they could ever possibly save by putting a 5 year old chip in a new system.
The real reason Sony is dropping the price of the PS3 is because of dedicated third party developers. Wii and 360 is selling like hot cakes and Sony is struggling to hit the 3 million mark. Notable third party developers are Square-Enix, EA Games and other developers that are cross platform have threatened to "focus" their attention on other systems as the PS3's sales have an even more marginal reflection on what types of software sales they can expect.
Most corporate executives see that the $500-600 price range was simply to overwhelming. It's not necessarily a bad cost to consumers in general, but the problem is the cost of competitive systems. It's not so much that a PS3 isn't worth $600. It's more so that the 360 is $300-350 for the top end model and the lower end model goes for $250-300. The Wii goes for $250 and has motion controllers. So it's more or less, parents, consumers and every day gift buyers see the Wii, a new system for $250. Or the 360, with games like Gears of War and Halo 3 on the horizon for $350 with coupons and rebates, and there's the PS3 for $500 at the least.
People naturally opt for the other choices.
Developers have been putting pressure on Sony ever since December. (In December Sony's sales were horrendous compared to Microsoft and Nintendo. Microsoft sold somewhere around 600,000+ units, the Wii sold something like 400,000+ units and the PS3 trotted far behind at around 180-190,000 units. Sony and its investors had high expectations of hitting the 1 million mark in US alone in December, but they didn't hit that mark in the US until late January, mid February.)
Sony is in a struggle right now. The PSP is actually carrying Sony's gaming sales, and with their fast decreasing sales in DVD players, televisions and surround sound systems, they basically need the PS3 to be a success in order for them to be around for a PS4.
This price is good for those that don't want to wait until Sony finally drops the price on the PS3.