Synching BL -> GR also sends my reviews, which is fine, but right now, in the first flush of bitterness, I would kill for a "truncate reviews" checkbox next to that gr sync button.
And this option would: Send the star rating, and shelves to GR. Send the first few lines, or say, 1-200 characters of the review to GR, and append a "Read the rest of this review and discuss at (insert-permalink)." Wouldn't that just be cute?
Right now I have GR synching turned on, feeding what I do here, to there. That is primarily for two reasons: GR still has better cataloguing capabilities, and probably will for a long time (aggregated all-editions-of-book or author pages, for instance, series handling.) Which is fine. The second is the GR Sync plugin that I use to synchronise shelves etc with Calibre (which is a lovely thing, because I have a ton of books I didn't even add there or here yet. Because lazy.)
Also, I'm thinking about a Booklikes plugin to Calibre - the api is pretty full featured, and it should be possible to do everything the GR one can do, here. But Calibre is python, and my python-fu is more like grasssnake-fu though - I fail to whitespace sometimes. So I ain't promising anything (but if any of you out there are python gurus, please consider looking at it.