Kinect does not need 8GB of RAM, and the Kinect team would not have been the driving force for getting that much memory into a system. You could get a significantly enhanced Kinect with 2-3% of that much RAM (and that would be more than 4 times the current usage, depending on features enabled)
I had deposited in the Alt. memory/storage thread this, to summarize:
Optical Media: (a) Size: Large (25-50GB), (b) Cost: Media is cheap, Drives are $40-$50, (c) Transfer: slow, in the tends of MB/s, (d) Latency: very poor at >100ms, (e) Other: They tend to be loud at high speeds and have reliability issues. Getting content from an optical disk into a game is the pits.
Hard Disk Drives: (a) Size: Large (250-750GB), (b) Cost: Drives have jumped into the > $50 wholesale range, game distribution only works with DLC, (c) Transfer: slow, but better than Optical, as it nears about 100 MB/s for best case scenarios, (d) Latency: poor at ~ 10ms, (e) Other: While HDDs cut down on transfer speed to memory they are still not exceptionally fast or quick. Serviceable although the idea of populating 4GB of memory from a HDDs averaging 20-50MB/s is still cringe worthy (80 seconds to fully populate at 50MB/s... yes, gameplay starting before load is possible but so are fragmented loads in the 10s of MB/s, too).
SSDs: (a) Size: Medium (60-128GB for console budgets), (b) Cost: Drives are expensive running up toward $100 but with some potential for cost reduction, game distribution only works with DLC, (c) Transfer: Good, in the hundreds of MB/s for best case scenarios, (d) Latency: Good at ~ <0.1ms, (e) Other: Some hurdles, especially in durability, in future reductions. SSDs are fast but they have limited size (100GB would seem small with caching for games on 50GB disks) so you are stuck re-loading content.
So what are we to do? The industry is at a rough inflection point. The future looks to be large SSD's with DLC, but that future is not today.
I had suggested a cheaper solution:
A ton of RAM. I even specifically recommended 8GB.
The idea that you could stream from your Optical Drive or HDD (or both) to a large RAM pool was this: One long load time, but enough memory that entire segments of games could be buffered into memory. So lets say each level is 2GB. You could start level 1 (2GB) and by the time you are done level 2 (2GB), level 3 (2GB), and level 4 (2GB) could already be sitting into memory. Cut it however you want (MP and SP and the next level loaded, whatever).
With 8GB of memory (a) Size: 8GB is large for memory so close to the processors; not good for long term storage but amazing for application use , (b) Cost: RAM has dropped through the floor, I have seen 4GB going for $25 and 8GB for under $50, (c) Transfer: Great, > 20GB/s, (d) Latency: Great in the ns range.
The only real issue is getting content into the RAM. But you are stuck with optical for distribution and optical and HDDs for storage anyways and a SSD, while a nice upgrade, is on the order of a magnitude SLOWER in bandwidth and latency than RAM. Instead of spending > $100 for a SSD why not spend an extra $25 to move from 4GB to 8GB memory and go with TSRs that state: gameplay must start within X seconds and then focus on content buffering. The idea you could access up to 8GB of content within a frame or two is pretty amazing.
That, right there, is why I think 8GB is a strong chance to being a real rumor. It is the cheapest trade off compared to a SSD, it addresses caching, buffering, and loading on a lot of levels (except initial load), and the performance benefit is WAY bigger than all the competing technologies. Getting bandwidth > 40x over a class leading SSD (and it gets only higher if the system bandwidth is over 20GB/s for the 8GB) and easily >200x over an optical drive (realistically nearing >1000) and the latency is a joke (e.g. RAM with 6ns latency = .000006ms; put another way 100ms optical drive latency is 100000000ns; RAM, not can be in the tens of ns of latency so 1x10^6 better if I did my math right).
Bring on the 8GB consoles
