I bought one of these today. It seems to be the original stories stripped down, then "re-inked" and colored to accomodate the nice white paper. Sort of cleaned up. I don't have a Marvel #1 reprint to compare it to at the moment. I dunno, sort of cool I guess.
If Marvel and DC systematically republished their old stuff in comic book format for $5.00 a pop (give or take) I'd buy every book they'd put out. The archives don't float my boat because there's no ads. People don't seem to appreciate that a golden age book is more than characters, writers, and artists. As a complete thing it's a chunk of history, a moment carved out in time.
Wait! There's probably some ridiculous copyright or trademark law covering the re-presentation of old ads that would make the whole thing illegal, immoral, and detrimental to national security.
I tell you, if Timely and DC were re-releasing their old stuff, I'd be camped out at a comic store. Fresh copies on paper? Man, paradiso.