Have tried the iPhone OS 3.0 Beta 5 for a couple of days now and am not too impressed. Tethering, Copy/Paste and A2DP were the main features I wanted to use early. Copy and Paste work.
Don’t install iPhone OS 3.0 Beta software if you rely on your iPhone (or iPod Touch)!
Tethering doesn’t work for me because I should have installed Beta 4 before and manually added the IPCC for my provider. The new iTunes 8.2 preview version that came with the iPhone OS 3.0 Beta 5 doesn’t allow adding an IPCC any more. Therefore MMS and tethering are still not available.
Bluetooth may work but I still had no time to test it with my car radio. So there’s still hope here.
Copy/Paste did me great favor already. Went to an exhibition yesterday where photos were prohibited. I couldn’t resist to take some pictures with my iPhone 3.0 until a guard caught me in the act and urged me to delete them. He wasn’t watching all the time so I copied the pics in Photos app – yeah, multi-select! – and pasted them into a new mail. Back in the Photos app I deleted them and everybody was happy again 
The original iPhone apps and 3rd party apps usually work but randomly crash at launch or when trying to access the internet. There are times when everything is fine but there are some hours when it keeps crashing on me. It reboots every now and then and the battery life has decreased to a few hours – 5-6h max. with all features deactivated. Some process is going berserk and heats up the iPhone.
Access to my Exchange mailbox has stopped working. It worked for 1 day, then suddenly I couldn’t access it anymore and the phone seems to keep trying since – it even seems to resume after a reboot. This blocks the whole device and I dunno what to do. There are still some options to explore but those will take some time.
There’s still hope for the Beta 6 and the final release.
Update:
At least I was able to fix some of the issues and now my iPhone 3G is back again working and usable as before. Apparently it ran into trouble synching with Exchange ActiveSync with Push enabled. This caused the Mail app to use all the CPU and the iPhone became slow (very slow) and most other apps were sluggish and unstable, too. And I could watch the battery draining within a few hours.
It was hard to get there but somehow I managed to delete the Exchange mail account in settings (Settings dialog kept quitting, too!) and suddenly the iPhone behaved normal. Everything was fast and stable. Even the battery life was restored normal and the iPhone cooled down. Before it felt really warm when you touched the back.
I really needed access to my Exchange mailbox and calendar so I gave it another try. It didn’t cause any problems to add my Exchange account and synching mails, calendar and contacts. Push notifications is activated and I’m curious how it’ll behave tomorrow.
At the moment my iPhone feels faster than ever but I could be wrong as I struggled with a unstable device for over a day.
