gdebi lets you install local deb packages resolving and installing its dependencies. apt does the same, but only for remote (http, ftp) located packages.

It has a graphical user interface but can be used in your terminal.

So far, I have only seen the gdebi source package been migrated to 'Testing'. How do we track if this package will be available as binary package?

Thanks.

Looks like it a binary package to me, at least it puts files into /usr/bin according to its package contents page on the Debian website.

According to the news section on this link,

[2006-08-22] Accepted 0.1.6 in unstable (low) (Gustavo Franco)
[2006-04-24] gdebi 0.1.5 MIGRATED to testing (Britney)
[2006-04-11] Accepted 0.1.5 in unstable (low) (Gustavo Franco)
[2006-02-04] gdebi 0.1.4 MIGRATED to testing (Britney)
[2006-01-24] Accepted 0.1.4 in unstable (low) (Gustavo Franco)
[2006-01-14] gdebi 0.1.2 MIGRATED to testing (Britney)
[2006-01-14] Accepted 0.1.3 in unstable (low) (Gustavo Franco)
[2006-01-03] Accepted 0.1.2 in unstable (low) (Gustavo Franco)
[2005-12-31] Accepted 0.1.1debian1 in unstable (low) (Gustavo Franco)
[2005-12-31] Accepted 0.1debian2 in unstable (low) (Gustavo Franco)
[2005-12-30] Accepted 0.1debian1 in unstable (low) (Gustavo Franco)

gdebi source package 0.1.2, 0.1.4 and 0.1.5 has been migrated to Testing. Does that mean that 0.1.2, 0.1.4 and 0.1.5 will only exist as source packages and not as binary package in testing?

Thanks.

That page you show tracks the progress of the source package it shows you on the left column (Binary Package(s) item) that a binary package named gdebi is built from it. Usually in Debian if a package(s) are source only they have -source in the package name like the nvidia-kernel-source, madwifi-source, .... these are source packages that you need to compile to get a working kernel module.

gdebi looks like a gui front-end for dpkg.

Can't you modify your sources.list to allow apt to use a local repository?