What's your choice of song(s) if you were to make a video of your transition?  Even though it's unlikely I'll need to transition, I still thought of a couple I'd like to use:

Semisonic - Fascinating New Thing
Badly Drawn Boy - Born Again

"Only Yesterday" by the Carpenters
That is the one that definitely feels like my transition's "soundtrack." It best describes the emotion that I went through pre-transition, then when I finally met my female self for the first time, and beyond.

If I were to pick actual background music for making an actual transition video on Youtube, though, my song selections would probably be the following:
Pre-transition: "April Come She Will" - Simon & Garfunkel
Transition: "I've Got A Feeling" - The Beatles, covered by BECK

And for the first one that I made, which was back at the 6-month mark, this was the one that I used as the introduction. I'm tempted to use it again, in its entirety this time.
"Across the Great Divide" - Kate Wolf

Not like I'll make one, but if I did it would definitely be "The Real Me" by The Who.

There are many important songs that make me reflect on my transition and events during it.  I don't think I'd ever make a video nor do I know if these songs are all appropriate for that sort of a thing but here is a list of meaningful transition songs for me.  These are sort of a soundtrack to my life, emotions and events that I've been through at this time and they are all important to me in different ways.  I'll have to make a cd in the future, lol.

Pet Shop boys- It's a sin
Dream theater- Learning to Live
Dream Theater- Far From Heaven
TLC- Unpretty
Anneke van Giersburgen- Wonder
Thrice- Artist in the Ambulence
Pennywise- Look who you are
Bad religion- Shattered Faith
Bad Religion- Who we are
Christina Aguilera- Reflection
The Verve- The drugs don't work
Brittany Spears- Stronger (okay, huge guilty pleasure that I will never fess up to liking, but it's my "i'll make it song").

For me - Let me be myself by 3 doors down
and Read all about it by Emile Sande

For a soundtrack to my transition would be:
If you leave me can I come to? - Mental as Anything
Death is not the end - Nick Cave version
Holy Grail - Hunters & Collectors
Devil's night out - The Mighty Mighty Bosstones

Definitely Call Me, either Blondie or In This Moment. Crap that is a song that is not really good, huh? Oh well, I need Brasso for my Halo anyway.