Hi guys,
No- the new trees are proper scenery objects and not splines. Creating tree splines was a hack that we used early on to lay a large number of trees without killing performance, similar to the "tree group" idea. It sacrificed flexibility for performance.
With the TS2009 approach to trees, creating a spline would now be a performance penalty rather than a performance boost. Since it's both better performing and more flexible to create single scenery objects rather the groups or splines, that's what we've done.
If you want to lay a large number of trees, the best thing to do is place a few down in whatever arrangement you might like, then use copy and paste to quickly replicate your work over a larger area. This approach allows you to build a forest in a matter of seconds.
chris