Best upload resolution

Hi gang!

I just have one question about uploading photos on the web. We all know very well that the 7D is an 18-megapixel camera, which means that every "RAW" photo file size hovers around 25-30mb depending on your camera settings at the time of exposure and has a 5184x3456 resolution. When I convert them to JPEGs from Lightroom 3 at FULL resolution (meaning I'm not downsizing them to 800x600, for instance) and then I upload that full resolution photo on Facebook or flickr, the image looks like it's not sharp (edges are a bit blurred). Even when I'm just looking at them on my monitor, they look unsharp. Please note that they look sharp looking at LR and PS5. I'm not talking about really unusable blurry shots. I'm talking about pics that are upload-worthy/bragging rights sort of pics.

How can I say that they are not as sharp as they should be? Because when I export them to JPEGs and resized them to 800x600, all of a sudden my pics are back to their sharp state. The difference is kind of hard to spot but it's there! You can see it clearly if you know what I'm talking about. I'll post an example if you want proof.

Now why is it important to me? Well, because I wanted to know if they be the same when I print them to say at 5R size.

My questions now are these:
1) Am I crazy uploading pics at full res?
2) Is it really just normal to resize down an 18mp photo before uploading on the web/viewing on the computer since 18mp is too big and monitors are too cramped a space for pixels to be represented at their full potential?
3) Is there any photo resizing technique that you know that you can share with me?

Please enlighten me fellas.

I upload to flickr at full res with great results.

when you upload to facebook, just resize so that the longest side is 700 pixels. I usually oversharpen the photo slightly too, because facebook sucks.

The Lightroom export/resize works just fine for me, and has the sharpening function that you can fine-tune to get the best results.

As you've noted, different sites handle resizing in different ways, and if you are not happy with the results it's really best to do it yourself. I'm not a Flickr user, plenty of people seem happy with the job it does, my host is pBase. What I do there is upload a photo that fits the rules for posting here on POTN -- 1024 pixels at the longest, and that "original" image is what I post on here for "sharing images". PBase then produces three smaller sizes for "normal" viewing and when I'm just tossing up an image for something quick I'll grab the "large" version which is 800 pixels at the longest.

So I'd say try different things, resize for FaceBook and maybe experiment with a smaller "original" with Flickr.

I limit all my uploads to 600 or 700 pixels on the long side, so that people are less able to steal them and use them in ways I don't approve. That's on Flickr, Facebook, in my own image galleries and anywhere else. It's big enough to see the image well, and will load quickly, yet not big enough to make very good prints, etc.

I also limit the size to 700 on the long side for the same reasons.