Our spouse visa took 5 weeks - we submitted our paper on January 11th this year and got the visa on Feb 13th. This period seems pretty much the norm at the moment
As soon as your wife gets visa she can join you , but remember she will need CFO stamp to travel - takes 1 day . Best place to get it in Manila is SMEF-COW center
As for refusal , provided you follow the UK visa guidelines , submit the correct papers , show you have suitable accomidation in the UK and can support her - I think there is very little chance that she or in fact anyone would be refused a visa . To think of it I dont think I've ever heard of a spouse visa gettind refused and as joebloggs says if for what ever reason it was refused , focus on that reason, I sure that can be resolved.
If you cannot resolve this yourself - contact your local MP and get him to petition the home office / british embassy . After all , under European Human Rights "A legally married man and wife has the right to live together"
