Nothing beats a good quality CAT5e or CAT6 network. Certainly not wireless and almost certainly not "homeplug" type devices.
Yes...and No.
Having worked at Nortel for 9 years and then another wifi expert company for 4 i'm sure I could show you some wireless that's faster, just as reliable, and easier to install than Cat5e/6
(but in general, you're right - which is why I replaced my Netgear homeplugs with Cat5E last month when I bought a new Samsung LED tv with built-in video streaming)
Incidentally, Netgear have just launched another set of Powerline adapters which are another step faster. We were beta-testing them for them for a while.
...oh and I too would concur on the use of fibre when going building-to-building. Also, lay 3 or 4 pairs - you never know when you'll need it, and it's as cheap as a single pair.