This: http://www.dot.gov/policy/aviation-p...onsumer-report
provided some very interesting information.

It appears that VX is FINALLY starting to price their product at a sustainable price level. I compared matching city pair data from Q4 2011 to Q4 2012 (4 matched) and found that VX's average fare increased by more than 10% on all four routes; a couple were in excess of 20%.

There were 10 city pairs that had average fare data listed for VX. I subtracted $11 from each fare to compensate for taxes/fees. The result was an average of 13.87 cents per mile. That gives VX a breakeven load factor somewhere in the mid-70s (using Q3 2012's CASM). VX reported domestic load factors of 81.10% in October, 74.52% in November, and 75.89% in December. No international load factors for Q4 reported yet; historically, their international load factors are lower than domestic but are less than 5% of VX's flights so that won't significantly impact the above load factors.

If these Q4 average fares are an indication that VX is finally starting to prudently price their tickets, VX should be around for quite a while. I'll go out on a limb here and speculate that VX will post its first Q4 operating profit. They'll almost certainly have a net loss, but posting an operating profit is a huge improvement.
Q3 and Q2 are VX's strongest quarters, so it may be possible for VX to have large enough net profits in those quarters to tide them over for their more difficult Q1 and Q4.

Bottom line: Based on this new data, I do not see VX closing its doors in the near future.