I don't think it will be that bad to change over from Aperture to Lightroom. You can export all your originals and versions in Aperture, then import them to Lightroom using the ADD option as described in the blog. The feature set of the two programs is pretty similar, too.
Don't get me wrong, I'm not happy with Apple AT ALL for discontinuing support of Aperture. It will cause a mild headache for me at some time in the future when I transition to whatever I use when I can't use Aperture any more.