There are pros and cons to the chapter idea. First the pros:
I like the fact that there will be new content out every 3 to 4 months. That means no more long waits between Aveyond games.
I like that you can ask Amanda to change the direction of the storyline, so that you can play a game that will end (or have the option to end) how you want it to (it would have been nice for RQ since I'm a Rhen-Lars fan;-) )
I enjoy the complexity of the storyline that causes it to be split into chapters. Complex storylines make for much more intriguing gameplay.
I like that life actually progresses in the chapter sequence, meaning that you won't go into a village in what should have been two days afterwards and the people are still telling you the same stuff. People are getting married and dying and such.
Now for the cons:
I don't like only playing a partial game at a time... I wish Amanda would have released the "full game" and then started the chapter concepts as "extensions" or some such thing. Like they did with the Diner Dash series when they created their "Lunch Packs". That way you have the option of buying the extensions or not, but you still have a full game to play.
When splitting the game, no matter how short of a time span in between releases, you are going to have the problem of people not being able to follow the continuation of the plot. They have to "get back into" the Aveyond mindframe and some info may possibly be lost.
I have always disliked the "To be continued..." Whether TV shows, movies, games, books, etc. that phrase is one to always make me rip hands-fulls of hair out. But, that is simply my personal preference and in no way a slander to those whose preference does not reflect mine.
These are simply my opinions on the matter. All in all I love all the games that Amanda has come out with so far and will continue to enjoy them for years to come I hope.