IMDbPro.com does include TV appearances. The layout of the two sites is a bit different and you may simply have overlooked them, but we list them exactly as on the regular IMDb.com site.
On the main page for any TV series, click on the "Episodes Cast" link (third from the top in the left hand side column).
See, for example: http://pro.imdb.com/title/tt0106179/epcast
Note that we no longer distinguish between guests and regular cast members.
To see TV series appearances for a specific individual, go to the person's page; up to five appearances in each series will be in their filmography. You can see all their appearances by either clicking on the "more" link under any series or by clicking on the "TV Series" link (in the middle of the "Filmography" section).
See, for example: http://pro.imdb.com/name/nm0000141/filmoseries.