When CI 3.0 stable version relase ?

There are only a handful of "issues" that affect CI3. We are in better shape than most of the other lauded frameworks ...
- Laravel has 277 issues in the core framework
- CakePHP has 116
- Symfony has 714
- phalcon has 525

What's your logic here?

The frameworks you mention are vastly more capable and have more features than CI.

You can't really compare Apples to Oranges.

Also, how long has CI3 been in "development"?  Will we actually see it in 2015?

If I was in-charge of this.  I would stick a fork in CI 3.  I would backport any reasonable updates to the framework and release 2.3 and draw a line under the whole sorry mess.

Start afresh with CI 4.0 and move on.