I agree with both Whizbang and Crothian. Yes, D&D can be expensive. Yes, there are alternatives. You can argue the pros and cons of each all day long and both will still be true. The gist of the thread seems to be lost somewhere along the way. I, like many others, loved the Rules Cyclopedia. It's really the book that made me a DM. I'd probably buy a new version of the book if it was the "final volume" of the 3.5e legacy. I would be less likely to buy it in a 4e form.
I know several casual gamers who gave up on D&D after the release of 3.5e. So many books, then more versions of the books, an excess of cut and pasted material, then Book X, Part II, etc. They found it ridiculous and from a certain point of view, it is. I didn't have such a dramatic reaction myself, but I did curb my purchases somewhat.
And, yes, there's always the SRD option. I've been online for years, I've been playing 3.0/3.5 since it's release, I joined ENWorld almost three years ago...and I've never used SRD. (Of course, I also don't own a cell phone or an iPod and I don't download music online. I'm archaic, I know.) Without a laptop or a great deal of printing, I'm not sure how practical the SRD is anyway. And it certainly isn't going to attract new players the way the old Rules Cyclopedia did. As for borrowing a book, well, that isn't always possible. The only other players I'm aware of in my town (heck, even my county) don't own any D&D books at all. (Well, there is one guy...but he scares me.)
Anyway, I think a Rules Cyclopedia would be a better way to introduce people to D&D than say the Basic Game approach. I don't use miniatures in my games and if you teach people to play with miniatures (or if they come to the game new with miniatures), they might end up thinking that you need miniatures to play. Great, more stuff to buy!
So, yeah. I'd bite. I ran a campaign for three years with nothing but the Rules Cyclopedia. It taught me the basics of D&D and, if it hadn't fallen apart from use a few years back, I'd still have it on my shelf today. My only concerns with a new version would be that a) I can't imagine WotC would ever release such a book, and b) it would probably not live up to it's predecessor if they did.