As Jura pointed out, what you will discover about a person online is basically only what they tell you - and it's easy to lie online.
Yes, you can meet many nice people online, but having them with you in 'real life' is a different matter. You can be online friends for years, but if you get to meet them in person, in some ways you are starting the friendship again, from the beginning.
Please don't trust the internet for short-cuts in your life. It has its limits also. ;)