No answers, just some thoughts...
How stable is megacorp? So many companies seem to be going under. I guess the PBGC guarantees pensions but I am not certain that they provide 100%. If I were in your shoes, I would be checking into that aspect of things. Then, if there is any doubt I would take the pension in 2009.
Notice that the increase from 2009-2010 is only 5.7%, scarcely more than inflation. But, the increase from 2010-2011 is a substantial 14.7%. That's interesting, and for me would tend to eliminate taking it in 2010. I would choose either 2009 or 2011.
Many different authors point out that the first ten years of retirement are critical, and that if a retiree can make it through those first ten years then investments will have compounded and grown, ensuring greater financial stability. Since your pension is not inflation adjusted, I would tend to think of it as a tool to ease you into retirement and get you past those critical first ten years (though I am not certain when you plan to retire, or if you are already retired). After 20 years, at 3.5% inflation your buying power will only be half of what it is now.
"You can never cross the ocean until you have the courage to lose sight of the shore." - - - C. Columbus