As far as I know HDMI does have some form of support for 4K, but don't expect eery piece of hardware to be run perfectly with such (if anything, the setup you describe will probably be bottlenecked at 1080p if it doesn't complain about resolution formats).
You will need a source that outputs at 1080p. Most cable boxes/ satellite boxes do not have the ability to output 1080p (Their native resolution being 1080i/720p) Blu-ray players including the PS3, the Xbox360 along with some other streaming video devices are the only way to get a 1080p signal on your TV. Keep in mind that your content will also have to be capable of 1080p. Some video games are capable, all Blu-rays are as well. A DVD in a Blu-ray player will NOT give you 1080p.
no
Negative, no networks broadcast in 1080P yet, it does 720P and 1080i
The main advantage of a laptop with a HDMI output is that you will be able to display video at a full 1080p resolution. Cable simplification would be another advantage, because HDMI can carry both audio and video.
1080p HDMI cables are available at mass merchants, such as Target and Walmart, as well as electronics stores like Best Buy and Fry's. Online outlets such as Amazon and Newegg also offer the 1080p HDMI cable.
Connect it to a 1080P HDTV with a HDMI cable and update setting for the HD Video
The Toshiba 46sI412u is already a 1080p LED TV. If you are using this TV with a cable box, you need to do fix the picture quality on the cable box. Some cable boxes will automatically detect the picture quality.
Yes. and it would be best to get HDTV even if you do have cable.
PS3 requires certain conditions for 1080P. Connection to a HDTV with 1080P capability with a HDMI cable and HDMI compatible TV set see related links
Ethernet cable or a special usb cable A-B
The HDMI connection on the laptop is for the same purpose as the connection on the PS3. They are both used to connect and allow the device content to be shown on an HDTV
The PS3 will upscale to 1080P if the system is set to upscale. You will not get 1080p you will get 720P upscaled to 1080P. I find that DVDs movies are better on the upscaled format, but they are not of the quality of Blu Ray.