Here is my opinion:
Spanish nationalism has one same tactics to "fight" against the other nationalisms (mainly Catalan, Basque and Galician), which is based on "divide y vencerás" (divide and you'll win).
Concerning the Basque-speaking lands, the application of this tactics consists in defending that Navarrans are different from Basques: they have different culture, different history, etc... (they don't dare to say they speak a different language because nobody would believe it). This is easy to do for them because the Navarran government has always been ruled by a Spanish-nationalist party, while the Basque one has always been Basque-nationalist.
This same tactics is repeated in Galiza (Galicia), where Spanish-nationalism is trying to cut off any relationship with their Portuguese neighbours. The Galician government has always been Spanish-nationalist, and actually, after 25 years of autonomous government, the number of people believing they share more than a borderline with Portugal has considerably decreased.
And, concerning the Catalan-speaking lands, this kind of tactics is our daily bread:
1) In the Valencian Country, left and right Spanish-nationalism has created during these 25 years an ideology defending that Catalan and Valencian are different languages. 27% of Spanish citizens live in a Catalan-speaking land, so the success of all this is really important in order to divide and weaken any possible conscience of unity among all Catalan-speaking lands. As an example, the <a href="http://blogs.periodistadigital.com/estebangonzalez.php/2005/10/28/p2634">Valencian Interior Councillor</a> called 'nazis' those who said <a href="http://www.normalitzacio.net/testimonis/index.php?sec=testimonis&n=1914">'Freedom for the Catalan-speaking countries'</a> at the end of a Barça football match, and said 'they behave like Germany when occupying the Czech Republic'.
2) The Balearic government has always been Spanish-nationalism too. But actually, movements of cultural and linguistic secession are not very strong there, where people have no problems to say they speak Catalan. However, during these last years, their government is trying to move away from Catalonia and their culture/language. An example would be their exit from the <a href="http://www.llull.com/llull/">Institut Ramon Llull</a> (the one which promotes Catalan culture and language around the world), and the consequent creation of the <a href="http://www.iebalearics.org/">Institut d'Estudis Baleàrics</a>. We could add another example: Catalan public TV <a href="http://www.tvcatalunya.com/ptvcatalunya/tvcHome.jsp">(TV3)</a> offered their videothèque of films in Catalan to the recent created Balearic TV <a href="http://www.ib3.es/">(IB3)</a>, but they didn't accept them, arguing that their viewers wouldn't feel comfortable with them, so they decided to broadcast all films in Spanish (!!).
3) In <a href="http://perso.wanadoo.fr/catnet/">North Catalonia</a> (<a href="http://www.cg66.fr/">Pyrénées Orientales</a>) there are no secessionist movements (we have enough trouble trying to preserve the language).
4) In the <a href="http://www.racocatala.com/~franjadeponent/">Franja de Ponent</a> (Catalan-speaking lands adminitratively belonging to Aragon), there is also a movement defending that's not Catalan, but "Eastern Aragonese". It is supported by some <a href="http://www.racocatala.com/articles/9509">local Spanish-nationalist governments</a>, and some Spanish-nationalist parties.
Among this atmosphere, the Valencian government created the Acadèmia Valenciana de la Llengua (AVL), which had to set a standard for Valencian Catalan.
Due to the secessionist ideology of their government, everybody thought they would create a totally new ortography, and a standard language as far as possible from Catalan.
But their members seem to be good philologists and this new standard seems to be quite reasonable, sharing the same ortography with Catalan.
I'm sure most people won't like this, and will say it is too Valencian, but I think it's right.
Oriental standard and Occidental standard (the Valencian one) are 100% intelligible, they just try to adapt to how people talks in each dialectal block without being too different.
such a long opinion!