The first corrections are rolling in. It is amazing that I can miss such obvious gramatical mistakes and misspellings, especially after reading and editing so many times (and with so many sets of eyes having read this before!).
There is no greater help to a writer than volunteers willing to read the work, to critique, to ask all the questions you thought you'd answered, to point out that a character's name is spelled one way in Chapter Four and a different way in Chapter Twenty, to tell you exactly how your science fiction science could never work. Feedback is essential. You discover just what you've accomplished versus what you hoped to accomplish. Then your job is to close the gap. (Or, in some cases, cast aside what you were trying to accomplish the first time because the readers saw something even cooler.)
Every day I get a little closer. Thanks, everyone, for the help and support. I hope to eventually thank everyone properly.