Last modified: 2013-06-18 16:28:17 UTC
Currently you don't know if your preferred username is valid or taken until you submit the creation form; at which point you probably have to fill out the captcha again. :P We should be doing a check via AJAX and providing clearer feedback about whether a username will work or not ahead of time.
Yes, I have just spent five minutes trying to sing up to wikipedia - and that was too tedious. Only good thing about that was that checking whether given username exists happens before checking captcha. I think this is related to https://bugzilla.wikimedia.org/show_bug.cgi?id=28085 - both make it harder to make an account and contribute more.
*** This bug has been marked as a duplicate of bug 34447 ***