Last year was definitely the year of the Kindle - we've seen a whole new generation of eBook readers come out, finally making this gadget category popular. To help you navigate the eBook reader waters, we spent the last few days compiling a table comparing some of the biggest eReader devices:

  • Spring Design Alex
  • Barnes & Noble Nook
  • Amazon Kindle 2
  • Amazon Kindle DX

If a category has a winner, it is highlighted in bold (in some cases there could be more than one winner).

Kindle DX features that are the same in Kindle 2 are marked with "<-".

Without further ado, let the best eReader win:

Alex eReader

Barnes & Noble Nook

Amazon Kindle 2

Amazon Kindle DX

Order of release 4 3 1 2
Release dates April 14, 2010 November 30, 2009 February 9, 2009 June 10, 2009
Internal memory 2GB 2GB 2GB 4GB
Expandable memory Yes - MicroSD Yes - MicroSD No - SD slot was removed <-
Average # of books that can fit in internal memory 1500 1500 1500 3500
CPU speed 624 MHz Unknown but in the range of 533-800 MHz 523 MHz <-
Screen(s) Dual, 6" E-Ink, 3.5" color LCD Dual, 6" E-Ink, 3.5" color LCD Single, 6" E-Ink Single, 9.7" E-Ink
Screen resolution 6": 600 x 800 px
3.5": 480 x 320 px
6": 600 x 800 px
3.5": 480 x 144 px
600 x 800 px 1200 x 824 px
E-Ink display Yes - 16 level grayscale Yes - Vizplex, 16-level grayscale Yes - 16-level grayscale <-
WiFi Yes - b/g Yes - b/g (+free WiFi at B&N stores) No <-
Global wireless (3G, 4G, etc) No but 3G, EVDO/CDMA, GSM support coming in a model that should be out later this year Yes - 3G Yes - 3G with fallback to EDGE/GPRS <-
Web browser Yes - on the color screen and the E-Ink screen Stock Nook - no
Rooted Nook - yes
Basic browser but a firmware update brought a more capable browser <-
Content sharing/lending No Yes, up to 14 days, between nook, iPhone, iPod Touch, PC, and Mac devices No <-
FM radio No No No <-
PDF support Yes Yes Yes <-
Formats supported EPUB, PDF, TXT, HTML, JPEG, GIF, BMP, MP3, MP4, Flash, 3GP EPUB, PDB (eReader), PDF, JPG, GIF, PNG, BMP, MP3 Kindle (AZW), TXT, PDF, Audible (Audible Enhanced (AA, AAX)), MP3, unprotected MOBI, PRC natively; HTML, DOC, JPEG, GIF, PNG, BMP through conversion <- + Audible format 4, RTF
Speaker Yes - stereo Yes - mono Yes - stereo <-
Text-to-speech No (confirmed to us by Spring Design) No Yes <-
Auto rotation No (confirmed to us by Spring Design) Unknown No Yes
Connector type MicroUSB MicroUSB MicroUSB <-
Battery capacity 3.7V 1530mAh (confirmed to us by Spring Design) Unknown 1530mAh <-
Battery life 14 days with wireless off,
6 hours with LCD screen on
10 days with wireless off 7 days with wireless on,
14 days with wireless off
<-
User replaceable battery Yes Yes No <-
Book selection Borders via Kobo, Google Books,
any protected ePub book from any bookseller
Barnes & Noble - 1,000,000+ paid and 500,000+ free books, newspapers and magazines Amazon - 450,000+ post-1923 and 1,800,000+ pre-1923 books at the time of this review <-
Synchronized last page read between devices No but promised later No but promised in early 2010 Yes <-
Operating system Android 1.5 (2.0+ coming summer 2010) Android 1.5 Linux <-
OTA (Over-The-Air) software updates Yes (confirmed to us by Spring Design) Yes Yes <-
Size 8.9" x 4.7" x 0.4" 7.7" x 4.9" x 0.5" 8.0" x 5.3" x 0.36" 10.4" x 7.2" x 0.38"
Weight 11 oz 12.1 oz 10.2 oz 18.9 oz
Price $399 $259 $259.00 $489.00
Buy it Buy It Buy It Buy It Buy It
 

Alex eReader

Barnes & Noble Nook

Amazon Kindle 2

Amazon Kindle DX

 

So, who is the winner? Cast your vote in the comments.

Sources:

P.S. Please report any errors - we did our best to post all correct specs but an error or two may have gotten through. Also, any clarifications for the "Unknown" fields are appreciated.