Encountered invalid key error on password reset. Discovered message emailed contained url delimited by angle brackets, and rightmost angle bracket was being included in login argument. Commented message variable and copied it omitting the offending bracket.
Ran into this issue, and removing the offending close bracket did the trick.
Oddly, only found my way here after Googling some actual code from wp-login.php there is no mention of WordPress 3.4.1 broken password reset email link easily found. Hope this helps, and thanks for posting.
Hey Seacostweb! I found your thread (about 1 year old) about your homepage loading twice or at least recording the hit twice because it loaded the header twice or something. Did you ever figure that out? I’m having the same problem and have not found anything about it except for your lone, unanswered thread …