I don't think it will, or can, "catch on" worldwide either, nor do
I think that's important for now. Nor do I find any value in
uniformity, which most of the other artificial languages assume is
the goal. Diversity is too valuable--I don't want one language
any more than I'd want one government.
But that's precisely why I like Lojban rather than all the other
proposed ALs: because it is so completely different from any other
human language in its core structure and utter lack--in fact
outright avoidance--of any recognizable human cultural artifacts.
I think learning it as a second language (or as a first one for
children along with a cultural one) cannot help but challenge the
cultural assumptions that all other human languages--including
artificial ones--are burdened with. Lojban is truly alien; it has
no nouns, verbs, or adjectives; no assumption of speaker or default
quantifiers/time tenses; no genders, familiar forms, or other
silly cultural baggage.
The fact that its grammar and phonology are unambiguous (though
one can certainly express ambiguous meanings--in a precise way) is
just icing on the cake, especially for computer/human interaction.
Not only by voice but for things like searching hypertexts where
Lojban words are never declined, and their function in utterances
is always parseable.
As for "spontaneous order", I think the current state of the
language embodies that quite nicely. The original genius behind
the creation of Loglan tried to maintain such complete control of
it that most of his students split off a group and redid all his
work with a new vocabulary and some new ideas, and specifically
released all proprietary claims to it, even paying to defend in
court their right to give it away. Lojban is now completely free
and open to individual change and evolution, with no central
authority of any kind to get in the way.