I’ve had 2 online relationships…one completely unsuccessful (my own fault) and one semi-questionable. You be the judge:
Relationship #1: When I first discovered the joys of the internet, I was a lonely single woman, recently graduated from college, and feeling quite isolated. And behold, the internet opened up a huge world of opportunity for someone who was a) female and b) able to string words together in coherent sentences. Fulfilling the criteria above to a T, I met this guy. This guy and I did the 0-60 in 2.3 seconds relationship thing. We talked, emailed, called, and basically decided that we were “in love” after about a week. By the end of the second week, he said that he was going to be in town about an hour from where I lived, and did I want to meet? Acting completely out of character, but convinced that I would absolutely die, Die, DIE!!! if I didn’t get to meet this guy, I went. And the whole thing seemed to romantic and impetuous, that I slept with him the first time we’d met.
Fast forward 3 months. The rush has abated somewhat, and I’m discovering quite odd things about my new beau…such as his proclivity for liking me to talk to him in bed. Which isn’t so odd…except for what exactly it was that he wanted me to say. Things like describing how I’d slept with all of the men in my office (I hadn’t…not even one), and what a slut I was. Ummm…warning bells!! Danger Will Robinson!! Danger!!
I broke that relationship off not long after that incident. It was just too creepy. In retrospect, it’s so obvious to me that I was so lonely and desperate for a connection to someone that I believed everything he said (including that he loved me) and ignored huge, gaping holes in the fabric of our relationship (if you can call it that).
Relationship #2: While the above relationship was waning, I met this guy in chat…he was in the AF overseas (I live in PA, he was stationed in England). We talked endlessly. We talked about everything. I’d never in my life met someone who I was able to talk to so openly and honestly about literally everything. We met IRL after chatting for 5 months. It was like we’d known each other out entire lives.
We’ve been “together” now for over 5 years. For reasons I won’t go into, we’ve never lived together. He’s been transferred 5 or 6 times in the 5 years I’ve known him, and it’s just not in me to be a tag-along. We’re both relatively independent people, and although the separation is difficult (we only get to spend physical time together a few times a year), the emotional relationship that we have is like nothing I’ve ever known.
This is not to say that we haven’t had our difficulties. He was hospitalized for depression late last year, and we didn’t talk for several months. We’re on the rebound now, though…although things are still being worked on. He’s out of the military now, and in a more permanent job. So, this one gets a big “we’ll see” at the moment.
Bottom line? Internet relationships are what you make them. Examine your own motivations. If you think you’re reaching out and connecting with people solely because you’re lonely and looking…I advise taking a good, cold, hard look at whether your most recent flame is really the one you were made for, or if you’re merely making that person who you think you need in your mind’s eye. I totally agree with the people above who said that internet relationships develop more quickly and intensely than IRL. When there’s nothing else for 2 people to do but talk, things get personal fast. I’ve always felt that my current SO and I were closer emotionally than people who were married for years, and lived together. The time apart forces you to pay attention to what each other says, as talking is all that you have. And it’s much more difficult to take people for granted, as it is when you’re physically together, but caught up in that daily grind.
IMO, internet dating isn’t much different than doing the bar scene. Of course, you need to pay just as much attention to what people say as you do IRL…keep your ears open for inconsistencies, verbal clues to attitudes that you don’t care for, etc. It’s true that you don’t have body language to read, but it some ways, it makes it easier to truly “hear” what people are saying…less distraction by how cute someone is. 
I’ve learned a lot in the past 5.5 years online. I’m far more careful with giving out personally identifying info. I’m way more reserved than I used to be…and I don’t take the adulation and “I love you’s” as seriously. Ironically (being that I was hopping into bed with someone I’d “known” for two weeks), I was extremely freaked out by how attached some people became to me, and so quickly. Part of it was being extremely uncomfortable having so much attention paid to me after being so lonely for so long…and another part of it was just a big “whoa…creepy.”
In any case…YMMV. Good luck. 
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