4gb ram w ssd vs 8gb ram w hdd

I'm hoping some recent AiR converts who used to have MBPs w 8gb of ram can chime in. I run a lot of apps at the same time (outlook, adium, skype, itunes, word, chrome w a ton of tabs open, fusion w xp for excel) and tend to use 6-7 MB of ram in my first day of use and if I sleep it overnight will be at 8 for sure by end of day 2. Since upgrading from 4 to 8gb of ram on my 2.4ghz 13" mbp it's been wonderful how much more stable things run and switching between apps is v nice. I want to get the new MBA and am concerned about the 4gb of ram. Will having the SSD for virtual memory make up for it? I read somewhere that virtual memory doesn't play well w certain ssd drives. I'm curious what the experience has been for people making the switch.

Thx!