So I have 4.0 on my iPhone 4 and want to use Jail break me, but my buddy says if I do not upgrade to 4.01, I am making a huge mistake. Thoughts on what I need to do, thanks.
Your buddy is telling you porkies! If you try to upgrade to 4.0.1, unless you have your SHSH on file, either on Saurik's server, or on your own computer, then you won't be able to upgrade to 4.0.1, as apple are only signing for 4.1 now. This would be worth checking before hand. As the person above said though, there really isn't any reason to upgrade to 4.0.1 as there is no real difference between the 2. Unless you think 1 extra bar on your signal bar is worth the trouble of upgrading...
In rural southern Ohio, 1 more bar might be huge, lol. So with 4.0 I can head to jailbreakme and do this, or wait until the "smoke clears"