Some people wanted to follow the progress, so I've created a task list for at least the book articles. The quick tour will be updated by #4374 and the cookbook will not be as important as these other 2 sections, they'll properbly follow after 2.6 is released.

I've ordered them on priority.

• Controller (fixed by Update most important book articles to follow the best practices #4427 and Completely re-reading the controller chapter #4433)
• Templating (fixed by Update most important book articles to follow the best practices #4427)
• Routing (fixed by Update most important book articles to follow the best practices #4427)
• From Flat to Sf2 (fixed by Update most important book articles to follow the best practices #4427)
• Page creation (see Update page_creation.rst #4685, Update page_creation.rst #4687 and Update page_creation.rst to focus just on pages, splitting other info to separate doc #4690)
• Http fundamentals (see Comply with best practices, Round 2 #4507)
• Doctrine (fixed by Comply with best practices, Round 2 #4507)
• Form (fixed by Comply with best practices, Round 2 #4507)
• Security (no changes needed, see Update book to comply with best practices #4431 (comment))
• Validation (fixed by Update book to comply with best practices, round 3 #4779)
• Testing (fixed by Update book to comply with best practices, round 3 #4779)
• Propel (fixed by Update book to comply with best practices, round 3 #4779)
• Http Cache (fixed by Update book to comply with best practices, round 3 #4779)