[Asus  Eee Pad Transformer Prime] jordache16:
1) Shut it down or not?

Personally, I always leave mine tablet running. There is a price to pay from a battery perspective when shutting down / starting up, so unless you know you are not going to be using it for an extended period of time, I would recommend leaving it on.

2) Services: my battery and OS responsiveness

I believe the 'Services' tab will show all the user app services that are running, but I am not sure if you can permanently prevent them from starting back up with ICS. I have seen task manager apps in the market that can prevent services from starting up. In all reality though, if you are concerned about background services draining your battery, the Prime has excellent battery life to begin with, especially if you have the dock, so if I was you I wouldn't get too worked up over the background services. Now if we were talking about a smart phone here (like my Thunderbolt for example which has horrible battery life), I would be much more concerned about this type of thing as I would want to do anything possible to squeeze as much life out of my battery just to get through an entire day.

3) Closing apps: should I care about it or not?

From my understanding swiping an app on the Recent Apps tray won't actually kill the process. Swiping an app from the Recent Apps tray more or less just removes the app from the list of Recent Apps. ICS automatically takes care of shutting down processes and releasing memory when appropriate. If you want to manually kill an app you can Force Close it from the list of apps from the Settings -> Applications menu. But again, my personal preference is to let ICS do its thing and take care of process management. I will remove apps from the Recent Apps tray just keep the tray less cluttered with apps that I don't use or need to switch to that often but I normally won't kill apps manually from the task manager.

On a side note, I would think removing an app from the Recent Apps tray would signal the OS that I am not going to be using the app again any time soon and the OS is free to shut down the process and release its memory, but I am not sure if this is what happens or not. All I know is that I have read elsewhere that removing an app from the Recent Apps tray will not immediately kill the process.

4) Launcher: Is ICS launcher the best for tablets?

Personally, I really like ICS so I haven't tried any of the other launchers that are out there (on the tablet side of things anyways). I used the GO Launcher on my phone for a little while but ended up switching back to the default HTC Sense launcher. This is one of the things I love about Android though; the ability to totally change the look and feel the device by simply customizing and switching between different launchers. If I ever get tired or bored with ICS, I can download a new launcher and just like that, everything will seem new and fresh again.

5) Tablet-optimized apps???

This is one of the big problems with Android and the Android Market right now; not just the small selection of tablet optimized apps but being able to find these apps in the Market. There is an 'editors top picks for tablet apps' section or something like that in the Android Market that I have used. Unfortunately, many of the apps in there are not that great, but at least they are optimized for tablets. Typically I will just do a google search for 'top android tablet apps' to get a feel for some of the best tablet optimized apps that are out there.