I'm going with CentOS, it is included with UNIX Academy training set

I got this set from Amazon and I'm on C right now. I like it.
http://www.amazon.com/Programming-Training-Beginner-Complete-Courseware/dp/B0052BF6YW/ref=sr_1_1?ie=UTF8&s=software&qid=1307625226&sr=1-1

I guess you're right, it depends on taste, Some prefer fedora and some debian, When no one controls the development, it starts organizing itself. Unfortunately it is not always optimal.

I'm on the same quest. First I tried some books. I collected as many as 24 of them (my entire shelve above a computer). Eventually I found that pdf documentation that comes with Centos (same as red hat) is better than any book I tried. It is very well written with clear instructions. I can follow their guidance even on subjects that I do not understand completely.
The real problem is the basics, not the advanced stuff. In every document they assume that you know some "minimal" Linux. The best training for this that I found is by unix academy DVDs for beginners. It is far from been Hollywood presentation, but it teaches you the right stuff in one week. I was following every lesson and example on the video for a week and it pays back as I passed first two unix academy exams. Now I can do all the essential stuff in command line and I'm reading red hat documentation. Next step for me is to pass two other exams with unix academy and than I'll be learning for Solaris certification.

It depends. If you're a beginner, I found that DVDs by UNIX Academy are better than any book for a beginner I tried, it takes you up to the speed in few days. For more advanced subjects I found book by Evi Nemeth "Administrator Handbook" is the best. I'm very good on Windows, I know it deep down to its guts, but I was pretty new to Linux until just few weeks ago. The DVDs are an amazing shortcut for learning all the basics. It solves a problem of been stumbled upon many basic issues. The DVDs teach many commands and explain how all the stuff works together. For more advanced learning, Evi's book is the best. You get very easy to read guidance on practically every advanced subject.

May be I'm wrong, but to my eye, eventually most of these branched out Linux clones will go away. There are too many.

I'm on a same path. In Linux as I see it, most important is learning the basics, the ropes of command line. At first it is very scary, but after that you can get on more advanced topics. I learn with training DVDs by Unix Academy and starting from absolute zero in about 3 weeks I learned a lot. By one person' recommendation I got a book by Evi Nemeth "Administrator' handbook" and it it very nice next step into it. After this initial push, the sky has cleared. I see there's much of learning ahead of me, but I'm set on a path.
Don't be set off by a horror stories. I didn't know what "shell" means few weeks ago. You spend time with it: you learn it.

So what loosing one (even key) developer puts the entire Centos project to restructuring?

Interesting, I have never heard of SL before...

Guys when you say "binary compatible" does it mean that all the commands have the same options and behave in a same way? I have been learning command line commands with UNIX Academy training DVDs and I see they have many options. My concern is, are these options are the same across Linux flavors or there are variations?