First off, youtube’s new maximum is called 3072p by industry-standard naming, not 4096p unless you rotate your monitor 90* and go narrower than the 4:3 standard, let alone below the 16:9 widescreen standard.

Secondly, it’s “up to” 3072p so youtube doesn’t need to modify their code every year that monitor resolutions improve. Currently a 1600p monitor is considered high-end, so you can’t expect google’s 3072 vertical-lines to be USABLE anytime soon; your house won’t have 3072p monitors capable of showing you all of google’s 3072 vertical-lines for at least 15 years at current rates (but VPU’s from ATi & NVidia might be able to drive 4 1600p monitors in about 5 years; BUT 4 1600p monitors will let you see all of google’s 3072p lines, which is only useful on a TV of approx 140″ or more, with an average viewing-distance of approx 40′ being comfortable for the average viewer…so unless you’re Bill Gates, I’d suggest that you save enough to add a room to your home that’s at least 50′ long (by at least 25′ wide), in addition to the costs of the 4 1600p monitors (of at least 70″ each… approx $4k for each of the 4 monitors if we extrapolate from today’s 1080p/70″ costs) AND the VPU capable of supporting 4x1600p, which when it comes out IN FIVE YEARS would cost approx $500-$1000. :-) That’s ~$17k BEFORE you even add the cost of dedicating AT LEAST a 1250sq-ft room [approx $125k in an avg US town] to your computer/TV pleasures. So you’d need to work approx FOUR YEARS at the median US income, without feeding/clothing/etc yourself for those 4 years, to pay for a space in which 3072p can be comfortably viewed…) Instead of resolution, there will be more focus from ATi/NVidia and monitor makers on achieving 42-bit color (or at least 30-bit should become standard, soon…), as the best pair of human eyes which experts could find can detect a 1-bit color-difference on a maximum of a 42-bit color-wheel, and because resolution of >1600p just isn’t that useful unless you have a huge screen and at least 50 friends that you feel a need to view it with at the same time. :-) A pair of Vuzix (VZX) glasses that each of your 50 friends buy for themselves will have better quality pictures at a lower cost… (or, to just rent a damn movie theater on the rare occasions that most of you will have a group of 50 friends who wanna watch something at the same time, would cost less than the $150,000+ that you’ll need for 3072p to be USEFUL in your home.

Lastly: “Also I did not see much difference between 1080p and 4096p resolution even though my laptop supports a resolution of up to 1680 x 1050.” You’re incorrect to say “even though,” it’s “BECAUSE” which is the opposite of “DESPITE” your screen having only that much resolution; we say “even though” when something unexpected occurs, and it’s TOTALLY expected and logical that your tiny 1050p resolution creates no significant difference . . . If you had a 1600p monitor, you’d see some difference (but even then, not the full 4096×3072). The only “difference” you saw on your 1050p laptop is
(A.) pixelization because neither 1080p nor 3072p are an exact multiple of the 1050 vertical lines on your monitor (but this can be corrected by firmware or software to a large degree), and
(B.) degradation because Youtube COMPRESSES THE FILES in a LOSSY format, and needs HEAVY compression to squeeze 3072p thru even an 8mbps (high-end/expensive) connection… only approx 5% of youtube users will have >8mbps internet speeds…
…and even 8mbps internet is approx 1/20th the bandwidth you need if you even want to match only a simple, old-style DVD’s color-depth/lack-of-file-compression, but then you wanted your DVD-movie to have all that picture-QUALITY scaled to play at 3072p RESOLUTION (without it being “fake 3072p” by using a line-doubler etc).