Okay, I am happy with how they portrayed this.
Very happy. It was properly updated without changing the foundation story much. They did change the pivotal character's name from Jan to Milo, but it still worked. I was very pleased that they did not show the Overmind as a being, and that they did not accidentally give it an age or a gender (by superimposing a dozen voices from different people from different ages and genders over each other). I was disappointed that they made it speak. Other than that, my minor issues with this three part portrayal of this story were not enough to take away from the deep meaning of the overall story.
I liked the three part series, but I LOVE the book a lot more. It may be Arthur C. Clarke's best novel.
I should also say at this point that it might be time to re-do 2001 A Space Odyssey (and 2010). The book is SIGNIFICANTLY different than the movie. Where the movie sorta drifts into an artsy, post-modernistic retro vibe...the book has a similar foundation to Childhood's End. But it's the book version of 2010 that is really out there. Especially the epilogue with the Europans. Im rambling...but obviously I am a Clarke fan.