I have the Transformer as well and it's been an interesting fight between my trusty Acer Netbook and the Transformer...
Short story? I still have and use both and still haven't really migrated to one or the other.
My Netbook is great. 2GB mem upgrade makes it usable for my tons of tabs, occasional Google Doc or LibreOffice runs - even can manage to edit the occasional Picasa photo without too much pain. It's a great form factor, the 9 Cell battery means long run times, and the screen is crazy bright (LED) - at night the dimmest setting can seem to bright. I may throw an SSD into it for fun. This has and continues to be my main 'away from the desktop' computer. I take it with me everywhere, bouncing WiFi off my phone when needed.
The tablet is interesting. First - the keyboard is not perfect. The keys are too far apart and I find myself having a lot of trouble typing on it, but that may be me. Either they require too much travel to 'tick' or my hands just don't fit it well. The touchpad is RIGHT under the space bar and I found myself clicking with my thumb ALL the time - I turned it off the first week or two and haven't turned it on since. All that said, I leave it in the keyboard almost all the time. I hate touch typing on the screen. But when I need the tablet mode, it's SO easy to just pop out and keep going.
The biggest adjustment (at first) was how many apps had no keyboard shortcuts. I'm a shortcut type - the less I need to touch a mouse the better. Simple Ctrl-C/Ctrl-V were foreign to many apps, which makes sense for an OS rooted in phones with no keyboard. The lack of support for some Google apps and other big ones on Honeycomb was criminal (No google voice? No netflix?) But to their credit the apps have gradually gotten better and better. More and more adding keyboard shortcuts they always should have had, battery life improving, and overall unlike most 'upgrades' anytime apps get updated you often notice the improvement.
To me the tablet is fun. LOVE watching full length movies and not seeing the battery meter drop in realtime or have the device almost too hot to touch. Playing Angry Birds is, of course, much more fun using your finger vs a touchpad. Email is just fine using the GMail client and web browsing with Dolphin is decent (too many other browsers default to mobile mode which is crazy with a 10" screen) Google Docs on Android is an abomination, but hopefully will improve.
So the tablet can take the place of my netbook for the basic email/web stuff and media viewing. Beyond that though? Not seeing it. At all. I'm just more efficient on my NetBook. Maybe that will change, but for now, I still find myself picking a device based on what I expect to do after work. Not sure that's bad, but seems inefficient.