They are really nice too.
Newer paper that feels thicker, if glossier. "Gilded" edges. Nice covers. These are nice enough to be collectors' items and still sturdy enough to be able to play with them.
The covers are a nice homage.
Gilded pages are always a nice touch.
It might be hard to see here, but the text is not an "exact" copy, there are some minor formatting issues. The books though have the same page count as before and my quick glance tells me that things that show up on page X in the old books still appear on page X of the new ones.
I also like the ribbon book mark.
This copyright statement and the new ISBNs are the only clue you will get inside that this was not a TSR publication. Many companies wold have altered the text inside to a degree I am sure. These pages, even considering they were completely re-done, are the same.
There is your history of D&D right there. Original Edition, Basic, Advanced 1 & 2 (and OSRIC), RC, 3.0, 3.5, Pathfinder and 4e. And my new books have a new home. That is till my kids see them in a couple of hours and they end up upstairs in their rooms.
I am not sure how much of my purchase went to the Gygax Memorial fund, but as long as it was some then I am fine.
Major kudos to WotC for getting these produced.