a good PHP framework is one that allows nearly every aspect of its design to be overridden. This really wasn't possible in some cases until recently with PHP 5 and abstract classes + interfaces.
Wasn't so long ago I got pasted by a few members who said that I were using too much abstraction... You can never really over use abstraction in my view, but I wasn't looking for an arguement that day, so I just let it go

Eventually the most popular, supported, and community-driven frameworks will win out, and the critical mass will be there.
This is why some frameworks in Java are way more popular than some of the others, the uptake is massive, simply because the framework (ie Spring for example) does exactly what the users are asking of it. PHP on the other hand, are all individualist frameworks, all doing their own thing, that of what the developer(s) wanted - not what the larger community wanted.

WACT is community lead for example, so maybe that'll make some inroads. Reading what Selkirk had to say on the mailing lists, of what some of the new stuff being developed, it sounds interesting.

There is hope.