This was
posted recently and has great answers to those questions:
http://www.sigmanu.org/documents/forty_answers.pdf
And yes, I went through a successful program that did not involve hazing but still felt that strong sense of sisterhood. Hazing breeds fear, resentment, and inbred idiocy. Holding sisterhood-building events (or brotherhood in your case) enables the new members to get to know one another, have fun, and live the principles of the new organization. Most GLOs were founded on sisterhood/brotherhood, academics, service, support, compassion, etc. Not hazing. We were not founded on wall sits and the ability to do wall sits does not make you a better member.
What mine looked like... We met weekly to learn about the sorority and chapter. We had casual lunches and dinners with our pledge class & actives. Actives decorated our doors with balloons and welcome messages. We had a sleepover. We did crafts projects (painted pottery, made jewelry, etc). We played games. We got to know people. We had fun. Nothing new and innovative there- we just weren't hazed.