As I'm sure most the geeks here are flashaholics some newbie may not be... so let's get a tutorial together for what can be done to minimize the negative impact of flashing. I'll update this post with links to content so anyone can follow the steps.
Before you do anything create an email settings CAB:
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1. Copy pim.vol to storage card or windows (this contains all your contacts)
2. Copy email settings CAB to storage card
3. Flash
4. Hard reset (not sure why but a lot of chefs seem to recommend this)
5. Install a file manager (like total commander or resco, most roms have one included)
6. Copy pim.vol over from your storage card overwriting file on your device root
7. Run email settings CA
8. Enjoy your new ROM
Hopefully this is useful (and not already covered) and some folks have some great ideas for speading up the flash process