I just activated the latest Simple Viewer WP Plugin v2.1.2. and on both mozilla and iexplorer my VM memory starts to grow starting at 400,000K.  My images only equal total 41,000k. Using WP 3.1

MY settings.
Gallery Title:  none
Image Source:  WordPress Library   
Gallery Style  Classic
Thumb Position   Left
Frame Width, 0 px   
Max Image Width,750 px  .
Max Image Height, 550 px   
Text Color ffffff
Frame Color   ffffff
Open Button  Fullscreen Button   
Thumbnail Rows  5
Thumbnail Columns  2
Gallery Width  800
Gallery Height   600
Background Color 
Background Transparent  no
Use Flash   yes
Pro Options  none