Another Perl conference, another naming/versioning discussion. Some thoughts on the topic:
I believe so: It looks and feels like Perl to me. Also note that while the Perl 6 situation with respect to its predecessor is rare, it has happened with other programming languages (e.g. Algol-68, Modula-2, even Python 3 to some degree).
Lot's of things.
On the language side, we've got sigil variance, its reference semantics, weak typing, no signatures by default and lack of a (usable) object system in core.
On the implementation side, we've got an unsatisfactory parallelism story, lack of JIT compilation and a 'fun' extension API.
These are technical issues: A new version number won't fix them.
Performance in general and performance of the regex engine in particular. Things have improved significantly, but it doesn't look good when your killer feature tends to be unusably slow.
The deployment story is unsatisfactory, though I'm hoping pamplemousse's Summer of Code work will help address this eventually.
Personally, I also consider the limited Perl 5 interoperability a defect: The Perl 5 community and ecosystem is a valuable resource instead of something to be eschewed.
These are technical issue: A new name won't fix them.
At the very least a standardized object system and signatures enabled by default. In principle, other language issues could be tackled as well.
I consider concerns about backwards compatibility or being stuck at version number 5 strawmen: Just choose a new naming and versioning scheme that does not conflict with Perl 6 (e.g. Perl2k 1.0) and add a new binary (e.g. perl2k) that enables all the goodies by default; the perl binary would be kept backwards-compatible, requiring appropriate use statements to enable new language features.
Better Perl 5 integration such as being able to embed Perl 5 code blocks into Perl 6 - I think getting something in place wouldn't be too hard (FROGGS probably could have implemented this proposal in a day or two on top of nine's admirable work on Inline::Perl5, which should be in core). I'd also like to see unified tooling (e.g. teaching zef and p6doc about Perl 5).