Moshe Vardi tells us that we all ought to join the ACM, partly to help support the main computer science society, but also because now you will receive the new redesigned Communications of the ACM under Vardi's editorialship.
ACM serves two very different communities, academic computer scientists and practicing computer professionals. The flagship magazine, CACM, has to cater to both groups to succeed. The old CACM mostly had articles around some common topic written by academics, aimed at practitioners and not fitting the needs of either group.
So how is the new CACM? The first redesigned issue (July) just came out and is available online. It hasn't reached the full vision but does give a taste with some opinionated pieces on topics from XML to quantum computing. It also has interviews with Donald Knuth and the Turing award winners.
Definitely an improvement but I didn't find any articles that truly excited me. If CACM hopes to become the "first magazine I want to read each month," it will have to take more risks, producing articles that give new perspectives to up and coming topics in computer science and lead the field instead of just reporting on it.