I recently acquired an Amilo M3438G through an HCI scheme.
Well specced laptop, almost good enough for a desktop replacement and will run most new games impressively.
Both laptops you mention have their pros and cons. The Acer has a newer Dual-Core processor, theoretically providing higher performance in applications that support it. The Fujitsu offers a Pentium-M processor...both will perform similiarly in a core-core comparison, but the extra core in the Acer may be useful in the future.
The graphics card is what seals the deal for me - the Radeon X1600 is a "mid-range" card, and while it should run the latest games, the 6800 in the Fujitsu would perform better. The "Hypermemory" feature on the ATI card looks annoying as well - the card itself has 256MB of onboard memory, but will eat a further 256MB from your system RAM to make the "512MB" it claims. I would rather have the system memory than the extra graphics memory.
Based on the graphics cards, I would go for the Fujitsu machine. You should be warned however, it's a
BIG machine.
Personally I think they've got a cheek to call it a laptop, but I love it
If the Acer machine had a better graphics card I would take the smaller screen and dual core processor however.