I did some research on this in the not-too-distant past and you can definitely tell that most television manufacturers are either including IP control or experimenting with it. Unfortunately, not all of them release the API for the control, meaning you are restricted to using their own applications (and thus are not an easy integration into Indigo).
What you want to look for is really dependent on what you want to get out of the integration - full control such that you know the states of the TV (power/what input is active/etc.) or simply a network remote that can issue commands/be integrated into a web page. Finally, you will almost definitely want to look for one that supports powering the device on over IP -- this is surprisingly missing on many TVs and models!
I worked with another user who had the foresight to look on Roomie's IP Control list to determine which models supported IP control and power on/off (of course this is usually available in the manuals, that is just a quick cheat-sheet).
Having said all that, I have two plugins that may interest you - one for Sharp AQUOS televisions that supports full control and can retrieve state information. The downside is that, at least when I released the plugin, they didn't have any small (30"-40") models in that line that supported IP control. That MAY have changed, I haven't looked in the last few months. The second one is to control Sony Bravia TVs (and, in theory, could control other Sony hardware such as BluRay, but that hasn't been tested). Unfortunately, Sony TVs do not report their state, so you cannot see what channel it is on, what the current volume level is set to, etc. The Sony's come in a better variety of sizes and have a nice picture, though, so worth a consideration.
You can see my documentation and sample controls in the 3rd Party Forum for my plugins...
http://www.perceptiveautomation.com/userforum/viewforum.php?f=59. I am not aware of any other plugins specifically for TVs, though I may have missed them.
Adam