If those statements are made by the issuer and are not factual, that is against the law.
For a private party musing about a stock, no it is not against the law, because someone is free to exercise their independent judgement as to any statement's veracity.
It only matters when it is the company disclosing information as they have a duty under Securities Law to be truthful.
However the company could pursue someone for libel, as a civil matter, but that is a VERY VERY high hurdle to get over. I am not familiar with a successful action in the penny world....and there have been A LOT of threats to do that by penny companies.
Edit: there is one other situation...if someone is paid to influence a stock and does not disclose that...it is also against the law.
The many many actions by the SEC against stock promoters are examples.
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