I definitely prefer the three-needle bind off (3NBO)
if it's appropriate (see next paragraph). I just tried it for the first time and loved the result!

I usually do the woven shoulder seam, but plan on using the 3NBO whenever I possibly can.
The type of seam you choose depends on how heavy the sweater is, and if there will be serious tugging on the shoulders. You don't want the shoulders to be more stretched out than the rest of your sweater. If you're making a lighter sweater, tank, shrug, etc. the 3NBO would be perfect and look very nice, very professional. ...and it's not scary to do!
If you plan on re-doing the shoulders on both sides with 3NBO, just use short rows. When you get to the end of the last row where you're knitting or purling up the wraps, your needle will be pointing in the direction it needs to be for the 3NBO. This is true for all four sections.
Some references:
The Knitter's Book of Finishing Techniques by Nancie Wiseman (pp.72-76)
http://www.knitty.com/issuefall04/FEATpatterns103.html
http://nonaknits.typepad.com/nonakni...row_shoul.html
http://www.purlwise.com/2004/03/post_4.html
and of course:
http://www.knittinghelp.com/knitting...s/bind-off.php
When you're ready to cast off with three needles, you can actually use the two ends of a circular needle in your left hand with a third needle in your right hand. I can't remember where I read this, but it is a great tip and prevents you from having to worry about having a third needle in the same size.
http://(That is of course only if yo...attern. :oops: