I think gaming is getting better, and I am having more fun as time goes on (and I get more into it), but in saying that the good games are becoming harder to find. I dont play shooters, or online, so I cant comment there. It seems these days that there are so many games coming out all the time of which you have to search really hard to find the good ones. Sort of a 'needle in the haystack' effect if you will. There are so many games these days that are so heavily promoted or have opinions decided for them long before they come out (eg the idea that uncharted 3 will be awesome, or the new Tomb raider will be disliked by all except 'fangirls like me) that it seems it creates even more disappointment when most of them arrive and fil to meet the lofty heights the magazines/internet/developers (in the case of obsessive self promoters like Bioware (case in point: Dragon Age 2 will be better than Baldurs Gate 2, joke of the decade!!!)) said they would. These days I commonly find the best games I played barely get reviewed (Ateliers) or overly harshly reviewed (Final Fantasies).
In my opinion I think its not a case of games not being as fun, but that there are a lot more not so fun games getting heavily hyped month in and month out. People buy these, more often than not get disappointed and start to believe that gaming on the whole is getting worse. Its the excess of quantity of releases (most not as 'cool' as the hype train promised) beginning to affect peoples perception of overall quality of all games
Thats just my opinion, I am Having great fun with gaming, more than ever in fact. I just purchase very few games and try to avoid impulse/hype related purchases I didnt really want that will just end up disappointing me (like L.A Noire).