The reason why we haven't seen any good looking third party titles until this year (Deadly Creatures, House of The Dead Overkill and Madworld have been very good in terms of eye candy imo) is because the success of the Wii took everybody in the industry (including me!) by surprise.
The majority of games during it's first two years of life were dodgy ports and mini-game collections that were rushed in a hurry to take advantage of a console's far superior marketshare, the shovelware will continue as it did for the PS2 in the console generation before it...some of those games were bloody dire lol. When the PS3 and the Wii were both announced everybody in the industry expected the Wii to be another Gamecube and the PS3 to continue the success of the PS2, so the majority of publishers ploughed money into PS3 development...the results of which we've seen during the last couple of years. And the majority of those PS3 titles lost money due to the console having a surprisingly low installed user base.
After Christmas 2007 it was quite clear with Wiis flying off shelves and with Wii development being cheaper than the other 2 current gen systems (a Wii Dev Kit will only cost a developer around £2000 for example, as opposed to around £18,000 for a PS3 Dev Kit
) that the Wii wasn't a fad and a great deal of publishers started to invest in Wii projects.
The great looking third party titles such as Silent Hill Shattered Memories, The Conduit, Dead Space Extraction, Resident Evil Darkside Chronicles, Gladiator AD and The Grinder show that with time and effort great looking visuals can combine with the Wii's superior control scheme for on-rails, third and first person shooters to provide a more in-depth and immersive gaming experience. It may not have the graphical horsepower of the PS360 but the titles I've listed above certainly come pretty damn close to 360 quality at least. People were mistaking The Conduit at last years E3 for a 360 title for example.
Okay off-topic rant over lol
It's already been leaked that Wii Fit Plus (with online play) and a Mario game of some sort will be announced later this week from Nintendo and it wouldn't surprise me if we get news of a Wii Zelda from Nintendo too - Link, swordplay, Motion Plus anyone.?
I'm expecting Factor 5 to have a WWI or WWII flying game announced after seeing the pictures of some of the buildings that were leaked a while back, and again this will have plenty of eye candy if Factor 5's previous titles are anything to go by.