One of the replacement models for the Acer Iconia A500 is supposed to be available starting today—the 10.1"
Acer Iconia A200. The 16GB version is featured in this week's Best Buy ad for $349.99 (the retail price), but Best Buy's website still states "coming soon" so I'm not sure if it's actually available in stores yet. Here's a link to Acer's
press release.
And there's yet another Acer 10.1" tablet on the horizon. It's the A700 model, which features a 1920 x 1200 resolution screen and quad-core 1.3GHz NVIDIA Tegra 3 processor.

Obviously, that model will be priced higher.
The new A200 seems to have the same features as the A500, except that there is no rear camera. The styling is a bit different (no metal strips top and bottom in the front). Personally, I like the new design better, although I'm a happy A500 owner and I have grown to like that design.
Here are the specs for the Acer Iconia A200:
1.0GHz NVIDIA Tegra 2 dual-core processor
1GB DDR2 memory
Android 3.2 Honeycomb (upgrade to Android 4.0 Ice Cream Sandwich coming mid-February)
8GB ($329.99) or 16GB ($349.99) internal storage
10.1" WXGA HD multi-touch display (1280 x 800)
NVIDIA GeForce
2.0MP front-facing webcam
dual speakers
802.11 b/g/n WLAN
Bluetooth
full-size USB 2.0
micro USB
microSD memory slot up to 32GB
microHDMI
1.5 lbs.