Dino, you're wrong about beta 1!
It seems like Dino Esposito isn't happy with the changes made to the AJAX extensions. I certainly agree with him when he says it's a new product. I also agree that it's relly a PITA to have a book which is being printed and already being somewhat out of date...however, I do think that several of the claims he makes aren't really true. Dino says that "The July CTP was a pretty good one and ready for Beta stage". I completly disagree with this. If you don't believe me, then take a look at the unofficial bug list posted by Garbin on the AJAX foruns. Several of those bugs are really show stoppers and made the previous CTP completly unusable in several real scenarios(for instance, the timeout of the login session cookie which was ignored by the UpdatePanel control). I almost agree with him when he says that "What we have now is a brand new start and is probably less than a stable alpha". As you might guess, I really don't think that the current release is less than a stable alpha...
He also seems confused about seeing 2 download packages. I agree that it would be really cool to get support for all the bits, but it seems like the team can't do that just now and that's why you get 2 packages: one has full support and other is given as value-added to the core bits. I'm not saying that the team shouldn't support everything...I'm just trying to explain why we have two packages (count on me to pressure the team to put more stuff into the supported bits!).
I'm not sure on what Dino is asking here:
"Which version should I study and teach? Both?
Which version should I recommend to clients and which to implement?
What if I have sites using July CTP? I feel comfortable only with Web services and UpdatePanel stuff"
If he's asking between previous CTP and the latest bits, then the answer is really simple: the last bits! Even if the team backs up and brings us some of the previous goodies, like for example, instance page methods (damn! goodies wasn't a well chosen name, specially when we're speaking about instance page methods :) - if you want to know why, then check it here), it's obvious that the latest bits are really better than the previous ones, even though they have less features.
If he's asking if he should look at the core bits or at the value-added bits, i'd really go with both, though only one is officially supported by MS. btw, there aren't really lots of changes between previous CTPS and the current version when you think in terms of web services and UpdatePanels, specially if you don't care about the internals (i admit that script injection from a partial postback is a breaking change, but easilly fixed in pages).
Dino goes on and complains about xml-script. I really think that there are still several things which could be fixed, but what I can say for now is that if xml-script doesn't work, then that's probably because of what i mention in this post. btw, xml-script is on the value-added bits and it has been improved in this last version, though it still suffers from several defects. I really see no ugly JS code on my AJAX pages and i'm really happy that i can easilly create new components with a simple method call ($create method). Yes, there are still some changes that could be made to the control API in order to simplify control creation (for instance, client validation could really be improved with the addition of a singe method to the InputControl class!). Regarding changes in the near future, I really think that maybe they'll fix one or two bugs and maybe add one or two things that existed previously but were removed from this version. I do really think that these last bits are great and a lot better than previous CPTs. And I hope that Dino isn't upset only because he's book, that is gone to priting, is already somewhat out of date....