I am also not a fan of the direction they have been heading since Mr. Jobbs passed away.
The regular MacBook Pro is pretty much the final stamp that is holding onto the older Apple direction. It is currently the only fixable/hardware replacable "all-in-one" that they offer. A lot of the hardware is now glued to the logic board - including the retina screen on the new MacBook Pro.
In my opinion, people that buy an MacBook Pro, or Mac Pro generally want the freedom to be able to replace parts if needed, as they are the more "premium" or "advanced" products that they offer. They are generally the items that a slightly more computer-savy person would buy. The MacBook Air however, I feel is more targeted toward the people that would simply replace a computer/laptop if it no longer worked.
Although they are basically letting the public decide their direction with the current MacBook Pro series.
Do consumers want a fixable, upgradable, product, or a aesthetically pleasing, non-fixable, non-upgradable product?
We see this in the Retina vs. Standard MacBook Pro's, as the standard is an easy product to fix, however the retina is glued in and difficult to fix.
*edit* Just on a side note, I am not making these posts to "convert PC users to Mac" as I don't believe that is right, or possible. I just hope to point out a few things that Apple do, both good and bad, that would help someone decide whether they want to look at using their products.
If you look at both items with an open mind, and an unbiased opinion, the answer is that both have their own place in the market, and that some people do actually benefit from Apple products being the way they are.
I for one used to be PC exclusive, until I started looking into what made Mac OS so great, and later learned from experience that Apple do indeed release quality products for specific areas of use. They do some things better then a PC, but a PC do some things better then a Mac. I believe that to be an undeniable fact.