Blu-Ray is not coming to Xbox 360.
Xbox Live Gold fee
check out my link (£2.33/month, instead of £4.50, this is me & my friend use.), its not free but then its a live maintained service using dedicated servers (except MW2 -.-) ... PS3 uses minimal servers & P2P hosting which is why lag is more prevalent.
HDD Storage on the 360 is ****, no doubt about that... a 700gb HDD can be picked up for £50-60, but a 120GB drive for the 360 costs about £100... complete rip off, i hope MS drop there prices or make it user changeable (without too much difficulty unlike the current process.) + the recent update allowed use of USB Memory Sticks & External HDD's (apperently.) but only upto 16gb.
WiFi, personally i'm glad they didnt put wifi in the xbox... yeah, its inconvenient.. but PS3 lags because its safe to say almost everyone on PS3 is using WiFi on unsuitable connections / routers / through walls / floors with alot of EM interference.... Xbox using a solid cable connection reduces lag, increases security, and increases bandwidth & then the Wi-Fi adapter is a premium price, so hopefully only people who know what there doing with Wireless-N devices know what there doing.