The whole "It's like calling English 'Germanic'" argument really doesn't make much sense (though we hear it often). It's like a false equivalence: English, German and Icelandic are hardly mutually intelligible and so it would no sense to lump them together under the label 'Germanic'. But Irish, Scottish and Manx Gaelic all have considerable mutual intelligibility, hence why it makes sense to view these languages as being a kind of dialect continuum.
What label should we give to this continuum? Well, the Gaels traditionally referred to it as Gaelic (at least that was before the ideology of the nation-state decided to tear this tradition apart, separating it into the categories of 'Irish', 'Scottish' and 'Manx').
Anyway, go maire Gaeilge na Gaeltachta go deo :)
