I wanted to compare solid-state storage options for my new laptop, and found some surprising results at tomshardware.com
Speeds in Mb/s
slowest-fastest read/write (a large image)
SDHC cards 2009 (8 to 32Gb)
12-70/9-47
Micro SDHC cards 2011 (8-32Gb) Class 10
1.5-3.4/0.01-1.37
USB 2 thumb drive 2011
11-35/3-20
USB 3 thumb drive 2011
33-125/23-139
src: http://www.tomshardware.com/charts/
Speeds seem to vary wildly depending on make and model, and I am surprised at how slow Micro SD is.
Just for further info, I wanted to get my head around transfer speeds of other technologies, so culled this list from Wikipedia.
General maximum bit rates
USB low speed … 1.536 Mbit/s
USB full speed … 12 Mbit/s
USB 2 … 480 Mbit/s
USB 3 … 5 Gbit/s
Bluetooth 1.1 1 … Mbit/s
Bluetooth 2 … 3 Mbit/s
Bluetooth 3 … 24 Mbit/s
Bluetooth 4 … 24 Mbit/s
Ethernet (10BASE-T) … 10 Mbit/s
Fast Ethernet (100BASE-TX) … 100 Mbit/s
Gigabit Ethernet … 1 Gbit/s (dur!)
Wifi 802.11b … 11 Mbit/s
Wifi 802.11g … 54 Mbit/s
Wifi 802.11n … 600 Mbit/s
Thunderbolt … 10 Gbit/s × 2
FireWire 400 … 400 Mbit/s
FireWire 800 … 786.432 Mbit/s
