I've never heard this story before, it actually makes sense, which does not means it is necessarily true. I'm not a big Pete Best fan but I know one thing is that true, they did sacked Best coldheartedly, and forgot about him. I guess the other 3 weren't then mature enough to handle this. Imagine how though it could have been to tell your band mate "we might just get a recording deal, if we get another drummer, that is" That's definitely something I wouldn't like to say to anyone. Also, I've always thought the the The Beatles (in their final lineup) were much more than the added talent of their individual members, they sort of multiplied each other; the final four were just the perfect group (sort of meant to be), and that would've never happen with Best (perhaps because of some of things this story says. If it is true, yes they could've jealous, maybe they didn't like Best's family being involved, etc.)
P.S. While Ringo might have been lucky, [in fact, all the other Beatles (final lineup) were quite lucky to find each other] he wasn't in anyway a lucky no-talent-johnny-in-the-spot:
http://web2.airmail.net/gshultz/bryant.html