Well, confirmed. iBooks will refuse to open. Since I read PDFs and books in there, that's a deal breaker.
Another deal breaker that's been confirmed is the current release of iFile will crash on startup. Bummer.
Other than that, many others are reporting the same issues I've seen:
1) After you install anything, instead of a "Restart Device" prompt, it'll be a "Respring" prompt. After you choose to do so, only Newstand is shown. There is no icon for any other app, and the application switcher wouldn't show anything else either. Hold Home + Power to fix.
2) If you get a "Restart Device" prompt instead, it'll take almost half an hour for the device to restart, which makes it seem like it froze on the Apple logo. Don't hold Home + Power or you'll have to restore.
3) Randomly, icons on the springboard would just blank (white) out. The only known fix is to restart the device completely (Home + Power).
4) Aside from iFile, a dozen other jailbreak apps are also not working properly, or at all.
5) If you're on 5.0.1 with semi-tether, you'll have to remember to uninstall semi-tether first, or you'll have to enjoy restoring the phone.
6) Restoring the phone still won't fix any of the issues mentioned.
Looks like a mess of a jailbreak to me. It's not the first time a jailbreak has had issues, but it's a first that a tethered jailbreak has had so many issues, at least to me. I think I'll simply go back to good ol' 4.3.3.