Macs I've owned:
2001 - PowerBook G4 TiBook
2006 - PowerBook G4 1.67 Ghz
2007 - MacBook Pro 8600M GT
2010 - MacBook Pro Unibody Core i7 2.66
I use the DVD burner almost every day on my computer. At my store we burn memory cards to disc for travelers. I refuse to carry around an external DVD for this purpose.
I use Ethernet infrequently -- several times per year -- but those few times when I need to use it are CRITICAL, such as reconfiguring a WiFi router at my business.
If they can shave 2 pounds from the weight, or even 1 pound, that is excellent. I am sure that the kind of nerds who come to this forum and who work at Apple rarely (if ever) use DVD or ethernet. Great.
However many of us in the real world (most of whom have never heard of macrumors.com and are too busy working to waste time on forums) rely upon technologies that are established, ubiquitous standards like DVD and ethernet because everyone has them.
The usefulness of a portable computer, to me, is contingent upon its ability to be a Swiss Army Knife of sorts. It needs to be able to interact with any situations that I might be confronted with as a professional photographer, as a small business owner, as a retail store manager, as an IT consultant, etc.
I am aware that external optical drives are now available that are compact and run off the USB bus. However that's one more THING to carry around, get broken, etc. I would prefer to have it "all-in-one" -- to me that's the point of a "desktop replacement" such as MacBook Pro.
Perhaps they will also have a thunderbolt-to-ethernet adapter or USB-to-ethernet adapter... one more THING to keep track of, which if you accidentally leave it at home, and the job calls for you to need it, now you are SCREWED.
Client wants all the photos burned to DVD. Oops, forgot DVD burner at home, or it's broken from floating around in my bag, etc. SCREWED.
Client needs Linksys WiFi router reconfigured. Oops, forgot ethernet dongle adapter. SCREWED.
I tell client, "Get with the times. You are so 2007." Never hear from client again. SCREWED.
I tell client, "Apple is a forward-thinking company, and your reliance on DVD and ethernet is quaint and laughable." Never hear from client again. Get bad review from client on Google. SCREWED.
Please, Apple, continue to offer the MacBook Pro in a DVD+ethernet configuration. I don't care if you also offer a MacBook Air Pro... fine, whatever... just don't screw over your long-time customers who need a professional tool that has these core, ubiquitous, standard technologies built-in.
Thank you.