I'm just speculating here, but I wouldn't expect to see a price increase until they move to the next major version number (ie V6). The good news is that because BI uses a paid support model for updates, the developers aren't trying to arbitrarily push out a major version release every 1-2 years to force people into buying the latest version because they stop supporting the "old" version. Instead, they continue to support and add new features to the current version and will only move to a new major release when it is warranted. The move from V4 to V5 was full of massive changes for example and it totally warranted moving to a new major version number.