Update 2011-02-08: After updating a second time (to the latest JPF firmware) with the SIM and memory cards in the phone, all my apps and settings were gone, this did not happen the first time (JPB firmware with SIM and memory removed).
Some minor roadblocks:
- Having to use Windows (for Odin)
- Having to install a driver in Windows to acces the phone, this step was missing from the how-to. Admittedly i used an ancient Vista.
- Seeing Odin report failure. Luckily, the phone was accessible right away and reported running Froyo.
- 3G, wifi, apps worked right away (it's probably a good idea to remove your SIM and memory card)
- Froyo supports USB tethering by default
- Has better UI for Gmail.
- Speech input for web searches.
- Boots faster.
- Everything is faster.