no php errors in output after changing file permissions

chowned /var/tmp/ to alexcannon, this is the upload_tmp_dir
chowned ~/Sites/ to alexcannon
chmodded 0755 /var/tmp
chmodded 0755 ~/Sites

http://stackoverflow.com/questions/8103860/move-uploaded-file-gives-failed-to-open-stream-permission-denied-error-after

But the file is still not uploaded, only output is:
Sorry, there was an error uploading your file.