I want to add a new defendant to a suit I filed before the tort reform changes went into effect. Since the suit was filed under the old rules, is everything (Expert reports, etc.) governed by the old or new rules?

Answer: Nobody really knows how most provisions of the new statute will be interpreted with regard to whether they apply to later amended cases but I think the answer will depend on whether the particular issue is procedural or substantive. If the issue is procedural, the new statute should apply. If it is substantive, the old statute likely will.