1. Bring first 5 ingredients and water to cover to a boil in a Dutch oven over medium-high heat, and boil 15 to 20 minutes or until potatoes are tender. Drain; discard rosemary, garlic, and bay leaves. Sprinkle potatoes with salt; gently stir to coat. Cool 10 minutes.
2. Meanwhile, sauté salami in a medium-size nonstick skillet over medium heat 1 to 2 minutes or until crisp; drain on paper towels.
3. Whisk together shallot and next 4 ingredients. Add 1/3 cup olive oil in a slow, steady stream, whisking constantly until smooth.
4. Cut potatoes in half lengthwise. Toss together potatoes, vinegar mixture, arugula, and tarragon. Add salt and pepper to taste. Top with salami just before serving.