I've done Oracle with RoundhousE on an application that's now in production.
RoundhousE is not a good fit for creating an Oracle database from nothing. The Oracle databases I've seen use a schema as the primary logical division; in other words, in Oracle, you'll use schemas in much the same way you would databases in SQL Server. Furthermore, the database itself is generally already set up, and you don't create new databases. This is thought of more like an installation step; you can't even form a network connection until the database is set up. Roughly speaking:
SQL Server | Oracle
----------------+------------------------------------
Server install | Server install & database set up
Database | Schema
So don't have RoundhousE set up the Oracle database. Assume that's already done; think of it as an install step. You wouldn't expect RoundhousE to install SQL Server or configure it.
That said, RoundhousE has a facility for specifying a create script. You might be able to leverage this to create your schema, but RoundhousE does not yet have the ability to specify a drop script (to my knowledge). You will need a separate tool for that.
I ended up using SQL*Plus Instant Client to manage creation and dropping of schemas within my build scripts: http://www.oracle.com/technetwork/topics/winsoft-085727.html. You'll need instantclient-sqlplus-nt-11.2.0.3.0.zip and one of instantclient-basiclite-nt-11.2.0.3.0.zip or instantclient-basic-nt-11.2.0.3.0.zip. (Newer versions are fine; just make sure you get matching versions.) Unzip them to the same directory. (On a side note, you can use the basic-nt or basiclite-nt instead of installing Oracle Client; you just need to make sure your application can find the DLLs.) You'll need to make command line calls for this to work. When RoundhousE gets drop scripts, I intend to dump this if I can.
Once you have a schema in place, RoundhousE works fairly well. Do check the bug lists over on Github and Google Code, though. There are a few weird issues. Once you get past them, though, it's well worth all the effort you've put into it. I wrote most of the database deployment build scripts almost 2 years ago, and they're one of the things that's stood the test of time on the project. They're written in PowerShell, though, so I don't know how this will fare in MSBuild.
Update:
In the years since I wrote this, Flyway has gotten popular. Consider using it or other tools, as they may have superior support for Oracle. RoundhousE hasn't fixed a lot of the issues that were identified several years ago. It seems primarily focused on supporting SQL Server.