faster/better development

[eluser]n0xie[/eluser]
[quote author="introvert" date="1274322699"]
1) debugging
Do you use any special library, technique which can make php development faster and more efficient?
Or you just define function log_me($str) ?
[/quote]
You have two types of logging. Error logging and 'general application' logging. Error loggers are good for Live environment. It should log when something that is supposed to work 'breaks'. General logging process flows, should give you some history in case something out of the ordinary occurs, without actually breaking the application.

When developing you should use tools like Xdebug to make sure your application works as expected. Unit tests and TDD are good in software development although I question the applicability in something as simple as a website, especially if you follow MVC principles. Most of my code that returns something to a controller (model, library, webservice) either returns the result, or FALSE. Either way it's something you won't catch easily with Unit tests.

[quote author="introvert" date="1274322699"]
2) code updates
I know about SVN and GIT and i know git is getting more popular and its faster. Which one do you use and why?
[/quote]
I would advice you to start learning git, even though the learning curve might be steep in the beginning. Git is gradually gaining more momentum, since it started a paradigm shift from single server SCM to distributed SCM. If you want to learn about the difference I would suggest you watch Linus Torvalds talk on git at Google. Coming from SVN I have to say, it took me a while to really 'get' git. It can be quite tricky and overwhelming at first, especially if you haven't worked with a VCS before or, in my case, you worked with a certain VCS too long. Some of the concerns are addressed on this excellent blog. What you notice is what most beginning git users go through. At first you hate it. As the blogger gets more familiar with git, his opinion slowly starts to change. Simply put, you can't use a tool like git and just use the basics. You have to really commit to learning how and why it does certain things (no pun intended). For insight read the series from that blogger, and especially this comment. I learnt more from that comment than all the tutorials online about git.