I will be biased here, but a good twitter background will engage more followers, it shows a seriousness and commitment that you will still be there in a week and not forget all about it! If you are doing a presentation on it, Twitter backgrounds are essential for twitter!
Kip FX Design - Twitter Background Tutorial | Kip FX Design is a background tutorial, but also tells you how and why you should use one.
If you get many people wanting one, I am sure we could come to some arrangement!
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