There are reports of IR still being an issue. Burn is a rare concept these days, but is a possibility in extreme cases. If you plan on using HTPC a lot than LCD/LED would be the way to go.
For general gaming and light HTPC use (no more than a few hours sitting on same screen) plasma would be a viable option. You would get the best gaming/picture setup this way.
LCD/LED cannot touch ms rates of lower end plasmas cannot be touched by LCD/LED.
If you are interested in LCD/LED for gaming/blacks your best options will be:
-LG LM7600 (lag could be noticable) 30-40ms
-Panny Et5 or e50 (Great ms for a LCD) 25-30ms
-Toshiba 6200u (reports seem to be good on ms lag but no confirmations from reviews/tests)
-Samsung es6100 or 6500 (again no confirmed tests for lag)