Would it scare you off or would you like it?

I like your use of "smitten" :) . If I like her, then I would definitely put her on my mind after she tells me that. I wouldn't go off thinking "OMG, she is a stalker!"

How well do I know this girl?

If she is a casual acquaintance then I'd prefer if she just asks me for coffee and tells me that she has liked me for a while and thinks I am a good guy, etc. Telling me that she loves me or secretly has been fantasizing about us then I'd say that is coming on too strong.

Now if I have known her for a while and she is a good friend, come to think of it, I'd still prefer just going for a coffee and her revealing her feelings for me slowly... It lets me digest the information in small quantities instead of having all feelings thrown at me at once.

Flattered

It wouldn't scare me off. Now, If she took it to another level beyond that like texting me all the time or calling me two or three times every single day then it would starting getting me angry, but what you're describing is not coming off to strong, in my opinion. It's being honest which I find nothing wrong. Even If it is a girl I didn't like, I would still enjoy it cause it boost my ego, although I wouldn't take advantage of that like other people I have met would do.

If this girl does this to me early in the relationship, I clearly have the upper hand and can take advantage of her if I want to. I think the time you should be saying that is at least after he says that he loves you. Cheers ^ ^

I think its best to not come on too strong with him until the relationship has a chance to develop and take hold. Then, if things get serious, tell him for sure. I always wanted to know exactly where I stood in a relationship. If you love him, let him know it! Often, and in many different ways! He will cherish you, and love you even more!

Take it in steps and don't throw a novel of feelings at him. Flatter him and tell him you think he's cute/handsome and that you've had your eye on him for a little while. And drizzle him with flattery and flirting, instead of pouring on all the feelings at once. See where you can take it. Build it up from there. And Timing, wait for the timing to be right to before you get too emotional. You know you like him, but you don't want him to interpret it as clingy or anything. And so it doesn't all just go to head.

Hmm interesting question. This problem of coming on too strongly is usually a guy's thing. But I supposed it can happen to a gal too. The answer to this question depends on two things: how much attraction I have for her and how she's asking

Case 1: little or no attraction
If he does it right, which is a subtle or neutral way, then there is a chance that I might be attracted to her in the future. If she does it in a wrong way, coming on as too needy/desperate, then I'd be turned off and there is no hope. But in either cases, I'd be flattered regardless of how she asked me.

Case 2: mild attraction
I'd repond to this case the say way I would to case 1. But I would be less turned off just because, well, I am somewhat attracted to her.

Case 3: a lot of attraction
If the girl of my dream or person of desire tells me that she's head over heel for me, I'd be very flattered and be turned ON by this. And assuming that I like her as much, I would think that she is 'the one" for me because she was thinking of me sooo much that she just couldn't hold back any more. I'd definitely try not to take her and her actions for granted.

Bottom line:
In any case, you should not blatantly tell someone that you like them that much. I think most people will think negatively(desperate, needy, etc) about you. You should only tell people that you love them this much when you two are deep into the relationship or in love. So how to tell someone you just meet or know that you are very very interested them them?

When talking to that person, give a warm and genuine smile and say "you know, I haven't seen many guys like you. You seem like an interesting person I'd like to know, so will you give that chance? "
That line does tell the other person that you like them at some level, but it doesn't tell how much. The way you say it is very flattering, and your style of approach is very modest/humble( another HUGE turn on).
If any girl said this line to me, I would definitely give her a chance(a date, number, anything). A woman of such modesty, humility, and respect(because she's picking only a few men to like and tell them that she likes them) will NOT be denied.

If I were you I would move on slowly, no need to rush, I know that you adore this guy a lot and may be loves him deeply too, take it easy and do it in a way that guarantee that he will give you the same feelings back. Us men some times we think of this as of winning a prize and then we simply move on and look for another prize to win, honestly do not express your self so fast, give your self and him some time, lets say you are in the middle of a relationship now then give it at least 4 or 5 months, if you give it more it would be better, try to find out his feelings toward ya, does he feel the same as you do! Are you both in love! Other wise you may get hurt badly because of this.

I know it is hard to keep all the love in you but you have to be cautious :-)