I would really like to see a tutoral on pollinating Citrus for the purpose of cross breeding. Hopefully, someone can help. I would like to try my hand at it. It would also be helpful to know which plant to take pollen from and to. Any tips of creating crosses would be welcome.

http://www.ehow.com/iphone/#article_2113437
also www.makezine.com/07/graft
I did alittle research there for you hope it helps in your quest
but as I see it takes ones career to make a hybrid exactly how you want it
good luck though

I'm know hand pollinating is universal in technique for the most part. What I am curious about, is choosing pollinators and hosts and how these choices effect the result. Does the fruit or tree that gets pollinated from another blossom carry a genetic upper hand?

For instance, if you are taking pollen from a lemon to a Clementine Mandarin, I assume Mandarin will retain it's size and shape, but the lemon will add some traits?

In your example, if the Clementine (or any variety) is the tree receiving the pollen from the lemon cross, it will still produce a true Clementine fruit. It is NOT the new fruit that is the hybrid, it is the SEED inside the fruit that is the hybrid. Further, if you do the exact same cross again and again, each cross could very easily produce different results each time. What your cross produces are new seeds with genes somewhere in between the two parents. Both trees are equal contributors. In the second link that David provided where it wrote about emasculating the bloom on the receiving tree, it failed to mention that this must be done BEFORE the bloom opens, in order to prevent the flower from self pollination. When the flower is full, but not yet open, and about two days before it opens, you need to gently remove the petals and VERY GENTLY emasculate the stamens before the pollen germinates. Finally, in most cases you will have to wait 10+ years for results, because the cross does not show up in the fruit, but in the seed of the fruit. Therefore, after the crossed bloom produces a mature fruit, you have to extract the seeds and plant them, then grow out the resulting tree until it matures and begins to produce fruit, to obtain the new crossed hybrid, this of course will take many years. For a containerized tree this could be up to a 15 or more year wait. I hope your young. - Millet (1,160-)

The easy way is to hand pollinate varieties that are seedless EXCEPT if they are exposed to pollen from other varieties. If You want to be 100% sure of your cross, you still need to bag the flower to prevent insect pollination of the flower you are working with.
The recipient should be a variety that reliably sets and holds fruit to maturity.

If you are young you will find that time begins to speed up, and you will wonder what ever happened to the 10 years, and your plant will bear fruit exactly when it wants to do so.

Millet, I know it's seeds, but I appreciate the input. I was curious if the plant recieving pollen carried a stronger weight in the new hybrid seed.