I still have my Toshiba FF1 ... bought as an early adopter at the start of 2006. 500g LED projector with mains plus 2 hr rechargeable battery pack, supporting 800x600 and 1024x768; also has fully featured remote (not that you need it). I paid £350 then - seemed a lot at the time, but it did (does) what it says on the tin, and is ideal for travel use.
Although the colours (particularly reds) are a bit harsh and lacking 'warmth', and the brightness means it really needs a dark room to shine, it is still quite possible to enjoy a full length movie running only on battery, with a projected image easily equivilent to that of a 60" Plasma screen ... and unlike the Acer in the review, it is almost completely silent.
I actually looked it up as I couldn't believe that this Acer is being touted as a new gizmo 3 years on ... http://www.wedgwood-group.com/toshiba_tdp_ff1_multimedia_projector.htm ... turns out the Tosh has been discontinued and they haven't replaced it with a similar spec.
I can only conclude that it is too niche a market (£300+ for a low res, low intensity projector is quite steep). The current netbook craze will no doubt give this an initial sales opportunity, but the old Tosh was a much better product IMO - if they couldn't find a market for it, I think Acer will struggle (particularly at the quoted price).