(Mac) Photogs, Aperture or Lightroom?

I've been using Lightroom 2.5 for awhile on my aging PC, mainly for organization and rudimentary post-processing. I use the presets a lot more than I'd adjust the levels and contrast individually.

My basic workflow is: Import to Lightroom->Selection and Processing->Export to JPEG->Upload to Flickr and/or Picasa

Now I have a much more powerful MacBookPro, I've been toying with the idea of either upgrading to Lightroom 3 or switching to Aperture. I am experimenting with both demos and found Aperture strangely unintuitive (probably because I'm used to LR), but I love its Flickr/Facebook/Email integration. [edit: ok, I'm an idiot, LR3 has it too now]

Any thoughts?

Personally I've been using Lightroom as it seems to have a much larger plugin market for expanded functionality. Jeffrey Friedl's blog is a great source for some excellent plugins that really expand on what you can do with the base product, also I find the interface for Lightroom more intuitive and it's less of a pig on resources.

They're both useful, but if you're already used to the Lightroom way of doing things I don't think I would switch.

My one sentence summary would be that Lightroom's editing is slightly more powerful, and Aperture's cataloging and keywording is noticeably better. But they're both in the ballpark of each other, and I can't see switching from one to the other without a specific motivation.

I went through this a while ago... used first light room extensively for the one month trial, then did the same with aperture. They are both very competent. I ended up with aperture as it was 99 for me when I was a student. Once you choose dont look back. You wont be missing anything. Just keep using/playing with what you have and you will learn so much more than comparing the 2 constantly.

as far as aperture (and lightroom I think) flickr, facebook, etc integration. The way they work is they maintain a consistent file version. So any editing or tweaking you do to the file post uploading will be synced to the uploaded file. This is pretty cool, but wrecks havoc with linking pictures in blogs.