Ahh, thanks guys. I was hoping someone would have the exact numbers but "definitely noticeably snappier" is good enough as a reason to upgrade.
Now how about the battery life, I was asking about the max. number of page turns and mAh in another thread but got no answers. Googling gives nothing on mAh and wildly varying numbers for page turns.
So can you people who upgraded from the 505 to the 950 tell me if the 950 lasts noticeably longer (without SD / WLAN) ?