I would say the standard for e-books is first right of refusal on derivitive works (sequels). Anything more restrictive than that I wouldn't sign.
I certainly wouldn't advise signing a contract that gives first rights of refusal to the next book regardless of subject matter. That's way too much to give up to an e-publisher in my opinion.
Though I've always wondered about first right of refusals and how they work in a court of law. Do they stay in effect only until the publisher accepts/denies a subsequen twork, or does the publisher get the right until the point in which they choose to accept a work? (i.e. if you sent in a horrid manuscript and they refused does that relieve you of your obligation).
I certainly wouldn't advise signing a contract that gives first rights of refusal to the next book regardless of subject matter. That's way too much to give up to an e-publisher in my opinion.
Though I've always wondered about first right of refusals and how they work in a court of law. Do they stay in effect only until the publisher accepts/denies a subsequen twork, or does the publisher get the right until the point in which they choose to accept a work? (i.e. if you sent in a horrid manuscript and they refused does that relieve you of your obligation).