@Linkat,
I think to 'love' someone, something, or someplace is to 'take delight' in him or her or it. I think wishing someone well is wishing them well - but to 'love' someone or someplace- to find being in their presence pleasurable or delightful - yes- I think you have to know the person or have visited the place.
You may take delight in the human race - but to state that you love a person simply because s/he's a human is different than delineating individually by unique personality traits that you find attractive or delightful.
Or at least it is to me. I wish everyone welll. I like the majority of people I meet, and I've never met anyone I've ever wished harm to come to- but I don't think this means I automatically love everyone.
And I've been to enough tropical islands to know that I love being om some and not others. The same applies to people (little joke there).
In terms of your specific example, loving someone on a2k that you've never met, I think it's definitely reasonable to say , 'I love the way so and so writes, or expresses him or herself, or I love the way they seem to know so much about....whatever'.
But I wouldn't be able to say I love someone unless I'd met them. I might be able to say, 'from what I know of you, I think you're someone I would find lovable' or something along those lines - but that's about as far as I'd be able to take it without meeting the person.