Fully Taped - Having outerwear with fully taped seams means that on the inside of the jacket all the seams are covered in tape to provide the most effective waterproofing. It can be considered a key feature if you live in a wet climate or are planning on wearing the jacket during heavy rains. The downside is that due to the full taping there is less breathability than you'd experience with critically taped seams.
Synthetic insulation is measured in grams, so a jacket with a 80g rating simply means that a 1 meter by 1 meter piece of that particular jacket's insulation weighs 80 grams. The higher the rating, the warmer the outerwear.