If history is any guide, that's a good deal for ADIA that will get paid back handsomely by the market -- not Citicorp. Don't forget their other angel, Prince Al-Waleed, put up $550M in the early 90s in a similar deal; those shares are worth ~$10B now. Ok, less in the last few weeks. But still.
I'm long-term bullish on Citi; this is a buying opportunity.
PREDICTION
Ok, I'll buy some calls tomorrow. Might be too late tho, now that this deal went through.
/jordan