2012 MBA vs 2009 iMac

[spoolup]

Hi guys,
I find myself and somewhat of a pickle.
I bought a 2012 MBA 13" (i5 1.8GHz) w/8gb o' RAM when it came out earlier this year.

I am not as mobile as I expected to be and all my "away" work can be accomplished with an iPad and a keyboard.

There's an offer to trade a 2009 iMac (i7 2.8GHz) for my MBA plus cash.

Here's what the iMac would be used for:
Brwosing/Email
Flash/Illustrator
xcode and maybe garageband.....

Would you recommend the swap based on the above?
Would there be any noticeable performance loss apart from not having an SSD (which will be added in due time)

Thanks in advance