MacBook Air vs. MacBook Pro

I need to purchase one of them. I love the aesthetics and portability of the MacBook Air, but I'm concerned that it won't be powerful enough to support what I do on a daily basis. For example, in a day I may need to run several applications; Photoshop, Illustrator, Outlook, iTunes, Text Mate, Filezilla, Word and Excel. Will the MacBook Air (with 1.7GHz Dual-Core processor) be strong enough to support these applications efficiently, or should I invest into a MacBook Pro with a quad-core processor? Any overall thoughts about the new MacBook Air?

Specs of the (new) MacBook Air I want to purchase:

  • 1.7GHz Dual-Core Intel Core i7, Turbo Boost up to 3.3GHz
  • 8GB 1600MHz LPDDR3 SDRAM
  • 512GB Flash Storage