This works for me in 12.10 for speeding up the scrolling.

sudo rmmod hid_magicmouse
modprobe hid_magicmouse scroll-speed=55 scroll-acceleration=1

You can play around with the speed. The min is 0 and the max is 63 (default is 32 I believe). Anything over 50 feels 'natural' to me. I used scroll-acceleration of 1; which feels like enough (when you move fast, scrolling is exponential).

If you dont' type them in right, the mouse will not be able to work until valid settings are applied.

I've had the same problem and recently I tried disabling eSCO mode in the bluetooth module:

echo 1 | sudo tee /sys/module/bluetooth/parameters/disable_esco
sudo /etc/init.d/bluetooth restart
# persist setting
echo "options bluetooth disable_esco=1" | sudo tee /etc/modprobe.d/bluetooth-tweaks.conf

The mouse's connection seems more stable now and I haven't seen a disconnect after tweaking this setting.

My laptop Lenovo W530 has a Broadcom Bluetooth adapter (internally usb is the interface).

If you have a Broadcom Bluetooth adapter, you might have to get a .hex firmware file from a windows driver and put it in /lib/firmware directory to support all Bluetooth features. More info in https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1065400/comments/11 and https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1065400 .

Use hex2hcd to convert windows driver .hex file to .hcd: https://github.com/jessesung/hex2hcd

I found Broadcom .hex files in this windows driver package. Locate the Win7/Win32/bcbtums-win7x86-brcm.inf file and search for the USB ID of your adapter.

$ lsusb |grep Bluetooth
Bus 001 Device 006: ID 0a5c:21e6 Broadcom Corp. BCM20702 Bluetooth 4.0 [ThinkPad]

search for RAMUSB<usb product id in upper case>, for example RAMUSB21E6 for my adapter. There you will find the .hex file name:

[RAMUSB21E6.NTX86.hw.reg]
HKR,,LowerFilters, 0x00010000, "bcbtums"
HKR,,%RAMPatchFileName%,0x00000, "BCM20702A1_001.002.014.1315.1387.hex"
HKR,,%RemoteWakeEnabled%,0x00010001,1
HKR,,%DeviceRemoteWakeSupported%,0x00010001,1

In my case the file was Win7/Win32/BCM20702A1_001.002.014.1315.1387.hex

I then used hex2hcd to convert the file to /lib/firmware/fw-0a5c_21e6.hcd (again that file name contains the USB ids of your Broadcom USB Bluetooth adapter).