Tamron AF 90mm f/2.8 Di SP AF/MF with Nikon D3100?

Would the Tamron 90mm lenses work with the Nikon D3100 regarding autofocus? I heard that the D3100 is at a disadvantage since it doesn't autofocus with many lenses and I was just wondering. Also, would you say that the Nikon D3100 is a good beginner DSLr?

It should be compatible.
According to
http://www.bhphotovideo.com/..._8_Di.html

Product Highlights

Compatible with All Nikon AF SLRs
Built-in Motor for Fast, Accurate AF

Here's a complete list of lenses that will autofocus on the D3100 and all other Nikon entry-level DSLRs.
http://en.wikipedia.org/..._19_lenses

Looks like that lens MIGHT autofocus, but check for the exact model as it is listed.

The D3100 is an excellent beginner DSLR, as it comes with a Guide Mode, designed to help beginners with typical situations and settings. There's a wide choice of modes for most common shots, as well as full manual controls to grow with.

True, like the D5100 and the like, it will only autofocus with newer lenses, but all new lenses coming out for Nikon cameras will work. It's only problem if you have several older Nikon lenses or have specific older optics that you want or need.

Here's some very detailed reviews.
http://www.dpreview.com/...nikond3100
http://www.kenrockwell.com/.../d3100.htm

And, with experience, here's what you may be able to do with a D3100. Feel free to examine over 35 million images to inspire you.