Izdanje je novo.

Because izdanje is a neuter singular noun, and the adjective has to agree with it.

• nov = masculine singular
• nova = feminine singular
• novo = neuter singular

So:

• nov grad = a new city
• nova knjiga = a new book
• novo izdanje = a new edition / release

In Izdanje je novo, the adjective novo matches izdanje in gender and number.

It is in the nominative singular because it is the subject of the sentence.

In a sentence like this:

• Izdanje = subject
• je = is
• novo = predicate adjective

The adjective novo is also in the nominative, because Serbian uses the nominative with this kind of to be sentence.

Je is the 3rd person singular present tense of biti (to be).

So:

• ja sam = I am
• ti si = you are
• on / ona / ono je = he / she / it is

In Izdanje je novo, je simply means is.

Normally, no.

In standard Serbian, in a regular present-tense sentence like this, je is usually required:

• Izdanje je novo. = normal
• Izdanje novo. = incomplete in normal speech, though it might appear in headlines, notes, or very poetic style

So for a learner, it is safest to keep je.

Serbian word order is more flexible than English, but je is a clitic, so it usually goes in second position.

That is why Izdanje je novo sounds natural:

• first element: Izdanje
• second position clitic: je
• then the rest: novo

You can also hear:

• Novo je izdanje.

This can sound more emphatic, like It is the edition that is new or The edition is new with focus on new.

But Izdanje novo je is not the normal neutral order.

Mostly, yes: the ending -e is a strong clue that the noun is neuter.

Also, izdanje belongs to a very common type of Serbian noun ending in -anje, such as:

• pitanje = question
• predavanje = lecture
• pisanje = writing
• izdanje = edition / release

These nouns are neuter, so they take neuter adjective forms like novo, dobro, važno, and so on.

Serbian has no articles like a or the.

So Izdanje je novo can mean:

• The edition is new
• An edition is new

In real use, the context tells you which meaning is intended. Very often, English has to add a or the, but Serbian does not.

A rough pronunciation guide is eez-DAH-nyeh.

A few helpful points:

• i sounds like ee in see
• z is like z in zoo
• da is pronounced clearly, with stress usually on da
• nj is like ny in canyon or Spanish ñ
• the final e is pronounced, not silent

So the tricky part for English speakers is usually nj:

• izdanje ≈ eez-DA-nyeh

Yes. Novo izdanje is the noun phrase new edition.

For example:

• Novo izdanje je skupo. = The new edition is expensive.
• Novo izdanje je stiglo. = The new edition has arrived.

But in your original sentence, novo is not part of the noun phrase before je. It is the predicate after je:

• Izdanje je novo. = The edition is new.

So compare:

• novo izdanje = new edition
• izdanje je novo = the edition is new

Yes, absolutely. It is short, grammatical, and natural.

It is a simple subject + to be + adjective sentence:

• Izdanje = subject
• je = copula
• novo = adjective describing the subject

It sounds like a normal statement someone might make in conversation, writing, or a review.