I wonder, if aimed right, will the best of our telescopes resolve an earth-sized planet near a nearby star?
No. The light of the star just blinds the telescope.
http://blogs.discovermagazine.com/badastronomy/2008/11/13/huge-exoplanet-news-items-pictures/ <=== This image that Notebook posted is the only one I know of that is possibly a planet. I've seen two images compiled into one, where you see a tiny shift in position from 2004 to 2006. Another image has been created in 2008 and I'm waiting for the compilation to be released...
The second image shows two really young planets. For one, the planets are still glowing from the heat of creation... and it's also likely that accretion hasnsn't finished yet, so they might still be giant blobs of hot stuff that will further collapse and lose size. They're easy to detect in infra red this way.
So you really have to be lucky to actually see another planet. We'd have to develop some really outstanding methods to actually separate the light of the star from the background and the planets for this to become a useful way of finding planets. So far the Kepler approach and the spectrometry approach seem to yield far better results.
You can see the huge shine from the star... you can also see the star has been cut out of the image. This time we're lucky. The planet is huge and orbits very far away from it's star. Usually we just wouldn't be able to see it...
---------- Post added at 10:06 PM ---------- Previous post was at 09:57 PM ----------
Oh, in the second picture on the site Notebook posted, you can see very young planets. Nobody really knows how long the accretion process actually lasts, so these two planets might still be just giant blobs of stuff that haven't fully collapsed into planets yet.
But the accretion is well under way - or very soon after finishing, so the planets are incredibly hot, which makes them shine in the infra red part... and are therefore easy to detect.