1. LUV stock gains 17% over eight days, valuing the company at $20 billion. 2. Analyst optimism on first-class seating and international alliances drives positive outlook. 3. Market capitalization has increased, indicating investor confidence in LUV's momentum. 4. Concerns arise from LUV's high valuation and weak operating performance. 5. Comparison with S&P 500 shows LUV's strong but risky recent performance.