I've been following this thread from the beginning and it REALLY makes me want to try JB!!!!!!! But it would be my first time doing it and I'm worried about the warranty issue.
QUESTIONS: If something went wrong with my phone or if I didn't like the JB, will a reset really take the phone back to stock?
Yes, just restore with iTunes
If I needed to take my phone to an Apple store, would they be able to tell that it used to be JB?
No, as long as you restored with iTunes and set up as new or non jb backup.
And if you JB, can you still use iCloud to backup the phone daily?
Yes, mine backs up just fine
How would it work if I reset the phone and went to do a restore...would it re-JB or would it go all the way back to my last non-JB backup and lose any pictures in between?
It would do the latest backup, jb or not. There is a consensus that one should not use jail broken backups as they may cause problems, but I have done it before on many devices without issue, though it should be avoided if the data can be restored from other sources
Also, does iMessage work on JB? I particularly like the read receipts and don't want to lose that feature.
Yes it does
Are there any other downsides I need to consider?
Battery life is impacted since tweaks run in the background. IWidgets are especially big offenders. Stability may be an issue, but usually tweaks work fine.
Any help would be greatly appreciated!!!
Hope that helps