Rainbow String Quilt

Although the tie-dye landscaping t-shirts will be a fun project, my major project this summer is going to be a rainbow string quilt. I've never made a quilt before, so I'm starting with a string quilt because I figure that it will be manageable to get all the blocks done - just lots of sewing in stripes. And, if I mess up the dimensions, it will be simple enough to trim all blocks to match. I'm not sure how good I really am at keeping a steady seam allowance, so that has to be an option. I want to make a queen-size quilt and I'll use the back of the current duvet cover that I have (from Ikea, turquoise blue) for the backing. I haven't decided whether I should just make a "quilt" duvet cover or whether I should go all out and make a real quilt. If I do make the real quilt, I'll also have to decide whether to do real hand quilting or to just tie it. I'm leaning towards tying - by the end of this project, I can imagine really wanting to get things done quickly, and I'm not really sure how to to hand quilt.
In any case, the top will probably be about 110"x110" - really large for a first quilt, but I think I can do it. I'm planning 11 blocks of 10" each, with each block done in diagonal stripes of two colors, depending on the placement of the block.
R O Y G B P B G Y O R
R
O
Y
G
B
P
B
Y
O
R
I drew up a sketch of how the colors look - I'll post it as soon as I can scan it.
This is going to be *amazing* - and so fun to make my first quilt! I'll be posting pictures of the blocks as they come along. I've already ordered some (really gorgeous) fabric - I'm figuring on 6 1/2yd lengths of each of the 6 colors - 18yds should be enough, with some left over for other projects. It's funny though, because generally string quilts are meant for using up your old stash, and I'm going to be adding to my stash with this project. But what can you do? I want this quilt to be just right, even if it means buying extra fabric. And once it's done - I'm convinced it will be totally worth it!
I don't have an exact plan for the arrangement of the blocks, but I love this quilt from snipnsew: