Very nice post. I'm 29 myself and I work as a consulting ergonomist, going from business to business. I'm confronted every day by people twice my age challenging me, and all of your tips apply : by being myself, being professional and having the skillset for the task at hand, age is really just a number. If you can hold out your own, you're recognized as a go-getter, "something youth is lacking sorely these days!".

Give me a break. If this was the middle ages I'd be 5 years away from dying of old age ;)