I think that it would be pretty hard to argue that there are no games that could be considered true works of art. The only real question now is how we define "art" in the medium of video games. Are all games art? Or just some of them? Does a game need only to have certain factors that are present in other mediums to be considered art (e.g. a strong narrative, distinctive or pleasing aesthetic qualities), or are there certain things that can only be done in games, and that must be done in games for them to be considered art? Unfortunately, gaming (especially artistically ambitious gaming) is such a young medium that there's very little precedent for analyzing these types of things. But here's my opinion on the matter:
Many games are art. Many other games, however, are just toys. The distinction is usually obvious, but it can get a little tricky when we start getting into games whose most important qualities are entirely unique to the gaming medium (i.e. old games that don't have much in the way of story or visual/aural presentation but have loads of interesting gameplay), so I'm not really going to get into that. However, it does lead me to my next point:
A game can be considered art for containing factors present in other media in a meaningful way, such as story (e.g. Metal Gear Solid) or aesthetics (e.g. your examples), but what's far more important for gaming's future as an art form and far more exciting for us gamers is when a game also utilizes the one artistic factor exclusive to video games: interactivity. This is still a largely unexplored frontier, but developers (mostly indies) are slowly starting to unlock the incredible potential that interactivity has for conveying artistic meaning. I defy anyone to play a game like Passage or Execution (they're both very short and free to download. Google 'em, and make sure you play Execution at least twice) and then tell me that the interactive qualities of a game can't make a person feel something or think deeply about something.
But those are just tiny little tastes of what's to come if we keep exploring the artistic possibilities of interactivity. In terms of more mainstream games, there are tons of examples of games that have moments of this kind of significant gameplay (e.g. Metal Gear Solid 4's infamous "microwave" sequence, the incineration of the Companion Cube in Portal, the nuke scene in Call of Duty 4) but fail to utilize them consistently throughout (e.g. most of the MGS oeuvre, which is practically a movie at times). Still, developers should be encouraged to keep making these kinds of moments, because if you think about it, you'll probably find that they're the most memorable parts of all these games.
As far as I can tell, there are really only three examples of games that I've played (that I can think of right now) where story, visuals, sound, and interactivity are all used brilliantly and consistently throughout the entire duration of the experience to form a cohesive and significant work of art. The first is Shadow of the Colossus, in which every strike of the sword comes with a pang of guilt, and the player gets a very real sense of Wander and Agro as characters through the gameplay. The second is Braid, in which the cryptic words, images, and even references to gaming itself turn out to have been intertwined with the gameplay all along, as revealed in an unexpected and jaw-dropping finale. The third is...okay, I'll just come right out and say it: I Wanna Be the Guy: The Movie: The Game. Why, you ask? Well, because to a certain extent, IWBtG is one of the first ever games whose genre can be defined as "comedy." Much of the humor is derived from the gameplay itself, and while "so frustrating it's funny" has probably been done before, only in IWBtG is it done in such a way that it cuttingly satirizes our idealistic nostalgia for the 8-bit days, where we neglect the fact that many of the games we so passionately defend were actually riddled with glaring design flaws.
Which is not to say that I don't encourage the industry to keep making games that are artistic in more traditional ways, too. I mean, the more games like Psychonauts, Metal Gear Solid, Mass Effect, EarthBound, etc., the better. But still, all just stuff to consider.
TL;DR- Yes.